---
product_id: 18494744
title: "Onslaught® FastCap Spider and Scorpion Insecticide | Indoor/Outdoor Concentrate | Commercial Grade | Labeled for Many Pests | Pint"
brand: "mgk"
price: "1027 kr"
currency: DKK
in_stock: true
reviews_count: 4
category: "Mgk"
url: https://www.desertcart.dk/products/18494744-onslaught-fastcap-spider-and-scorpion-insecticide-indoor-outdoor-concentrate-commercial
store_origin: DK
region: Denmark
---

# Fast-acting kill Botanical-based tech Indoor & outdoor use Onslaught® FastCap Spider and Scorpion Insecticide | Indoor/Outdoor Concentrate | Commercial Grade | Labeled for Many Pests | Pint

**Brand:** mgk
**Price:** 1027 kr
**Availability:** ✅ In Stock

## Summary

> 🚫🐜 Outsmart pests fast — because your home deserves a no-creep zone!

## Quick Answers

- **What is this?** Onslaught® FastCap Spider and Scorpion Insecticide | Indoor/Outdoor Concentrate | Commercial Grade | Labeled for Many Pests | Pint by mgk
- **How much does it cost?** 1027 kr with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.dk](https://www.desertcart.dk/products/18494744-onslaught-fastcap-spider-and-scorpion-insecticide-indoor-outdoor-concentrate-commercial)

## Best For

- mgk enthusiasts

## Why This Product

- Trusted mgk brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Pet & Family Friendly:** No harmful residues or odors—peace of mind for homes with pets and kids
- • **Rapid Knockdown Power:** Eradicates spiders, scorpions & pests within minutes ⚡
- • **Versatile Application:** Safe and effective for both indoor and outdoor environments 🏠
- • **Trusted Legacy Since 1902:** Backed by over a century of botanical innovation and expertise
- • **Advanced Synergistic Formula:** Combines esfenvalerate, prallethrin & PBO for unmatched pest control 🌿

## Overview

MGK Onslaught® FastCap Spider and Scorpion Insecticide is a commercial-grade, fast-acting concentrate designed for comprehensive indoor and outdoor pest control. Featuring a powerful blend of esfenvalerate, prallethrin, and piperonyl butoxide, it delivers rapid knockdown of spiders, scorpions, mosquitoes, and more. Trusted since 1902, this botanical-inspired formula offers safe, residue-free protection ideal for residential and commercial settings, ensuring a pest-free environment without compromising safety for pets or family.

## Description

MGK 10085 Onslaught FastCap Spider and Scorpion Insecticide, Off-White

Review: It’s works for scorpions, tarantulas, and whatever else is creeping around Texas hill country - Don’t know what’s different about this year than all the others, but the scorpions are out with a vengeance. It’s seriously not fun. We’ve had them in our bed, in the dog beds, in the bathrooms, in the kitchen, in bedrooms, in the living room, on the ceiling, and the list goes on and on. Truly awful, and it was showing no signs of relief. We had been using Wondercide indoor pest control cedar scent spray, which did help, but didn’t solve. It smells great, which is a bonus, and is totally safe for us and our pets, which we love. But again, it didn’t eradicate the scorpions from our home. We tried the traps. Again, they work and serve their purpose, but they don’t stop the scorpions from entering, they only help catch them once they’re in. So problem still not solved. We’ve also tried other things: cedar wood blocks and chips everywhere, peppermint and other heavily scented scorpion deterrents, etc. No dice. We really tried to stay away from insecticide, because of how many animals we have, but we were at the very end of our rope. There aren’t many options when it comes to options that can kill scorpions. So this what we went with. We followed the directions and sprayed outside the night we received it. When we woke up the next day, it was like a graveyard out there. Dead bugs everywhere. Not just scorpions, but stick bugs, beetles, stink bugs, June bugs, a variety of spiders (including tarantulas!), mosquitos, crickets, and other things I couldn’t even begin to tell you what they were. Since then, we’ve also sprayed inside, and have found three dead scorpions, three dying scorpions, several new dead scorpions in the traps, and now, about a week in, no scorpions for two days in the house! One I found the first day that was still kicking, I grabbed him with my tweezers and put him in a bowl, then sprayed him. I watched him squirm for about 15 seconds, before he flipped over on his back and died. Just like that. Just stopped, flopped, dead. Also, we run a dog rescue here, and we have 19 dogs. During the day, the dogs are mostly outside in the yard and/or in their outdoor kennels. Since spot spraying and spraying the trees outside, there is a dramatic decrease in the amount of flying insects. >90% decrease in flies, mosquitos, moths, and June bugs. Amazing! So far, no ill effects on us, the dogs, the reptiles (snakes), amphibians (frogs), or small critters outside (bunnies) at all. No impact on the landscaping, no residue or discoloration left on the carpet, walls, or floors. No smell, except maybe a very faint buttery smell when it’s very first sprayed. It’s easy to mix, since the container has the built in measure, and you only need .5-1 ounce per gallon. That’s 16-32 gallons with this 16oz bottle. That’s a great deal for so much peace of mind! This stuff works. It’s safe and easy. Just follow the directions. Don’t over mix it (no need to waste it), make sure to let it dry completely before people or pets touch it, and you’ll be all set.
Review: My personal experience along with an experiment and direct comparison to Harris Scorpion Killer - Scorpion season started earlier this year in South Texas. Ordered this after reading reviews for multiple days and feeling confident that it will help us. Morning started with us finding a scorpion in the laundry room. We caught it in a glass and sprayed one part of the floor with Harris scorpion killer and the other part with Fastcap scorpion killer and waited for both sides to dry. Sat the scorpion on the Harris side and turned the vase over it so it can be controlled on the treated area. Let it run around for about 30 seconds (seemed a reasonable time for it to naturally cross over) and scooped it back into the vase. Watched it for about 2 hrs happily crawling around the vase. No lameness no twitching. Just alive. Time for the second test. This time sat it on the fastcap treated area and again let it run around for 30 seconds. Scooped up and watched it. Here is what happened after exposure: After 2 minutes he got really really slow and we saw right away something is effecting him. After 5 minutes he started acting like a drunk. Uncontrolled body moving, legs kinda tried to crawl in the air and the tail bent over its body. After 10 minutes he flipped on his back and started twitching like crazy. Then nothing. Legs curled up, tail went straight and no movement at all. I moved the lifeless body around in the vase to test any reaction- NOTHING! Watched him for the next 3 hrs. Checked about all 20-40 minutes. At the beginning there was still some slight movement in the legs and pinchers here and there but you could definitely tell it’s just muscle spasms. After 3 hrs I disposed of a dead scorpion. To be fair, he was first exposed to Harris but lived on. Not saying that didn’t somehow affect him but after exposure to fastcap it went very quick. After that I sprayed my entire inside of the house. Under the sinks, behind washer/dryer and along all perimeter of the inside. It’s raining but as soon as the rain will stop I will spray generously outside up the siding and along the base and grass surrounding about 2 feet of the house. My goal is to knock em out the way I saw it happen today before they even get the chance to find an entry point. I’ll probably repeat my experiment with fastcap in about a week to see how the stuff works after some time and will update my review then. For now all I can say is I am happy seeing first hand that it kills these crustaceans fast and am looking forward to report the effectiveness in a couple of days regarding the left over strength HOPEFULLY less scorpion sightings. Before any treatment we found 6 within 7 days.

## Features

- CONVENIENT PEST CONTROL: Protection against a wide range of residential and commercial pests populations including spiders, scorpions, fleas and mosquitoes.
- QUICK KILL: Onslaught FastCap Spider and Scorpion Insecticide offers a convenient and approach to pest control.
- INDOOR AND OUTDOOR APPLICATIONS: Effective pest control in and around livestock facilities, on turf, ornamentals, landscapes, and in food and non-food areas of commercial and residential structures.
- ACTIVE INGREDIENTS: Combines esfenvalerate and prallethrin with synergist piperonyl butoxide (PBO) for fast-acting pest control.
- A LEGACY YOU CAN TRUST: Driven by expertise and industry commitment, MGK has been developing pest control products based primarily on botanical and innovative technologies since 1902.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0093NBOBE |
| Active Ingredients | Esfenvalerate,Prallethrin,Piperonyl Butoxide |
| Best Sellers Rank | #8,870 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #160 in Insect & Pest Repellent Sprays |
| Brand | MGK |
| Customer Reviews | 4.7 4.7 out of 5 stars (1,338) |
| Department | pest control |
| Is Discontinued By Manufacturer | No |
| Item Form | Spray |
| Item Weight | 1.2 pounds |
| Item model number | 10085 |
| Liquid Volume | 1 Pints |
| Manufacturer | MGK |
| Product Dimensions | 4.25 x 2 x 8 inches |
| Target Species | Insects |
| UPC | 848920000492 |

## Product Details

- **Active Ingredients:** Esfenvalerate,Prallethrin,Piperonyl Butoxide
- **Brand:** MGK
- **Item Form:** Spray
- **Item Weight:** 1.2 Pounds
- **Liquid Volume:** 1 Pints

## Images

![Onslaught® FastCap Spider and Scorpion Insecticide | Indoor/Outdoor Concentrate | Commercial Grade | Labeled for Many Pests | Pint - Image 1](https://m.media-amazon.com/images/I/61b3tA-tnNL.jpg)

## Available Options

This product comes in different **Style** options.

## Customer Reviews

### ⭐⭐⭐⭐⭐ It’s works for scorpions, tarantulas, and whatever else is creeping around Texas hill country
*by N***. on June 20, 2024*

Don’t know what’s different about this year than all the others, but the scorpions are out with a vengeance. It’s seriously not fun. We’ve had them in our bed, in the dog beds, in the bathrooms, in the kitchen, in bedrooms, in the living room, on the ceiling, and the list goes on and on. Truly awful, and it was showing no signs of relief. We had been using Wondercide indoor pest control cedar scent spray, which did help, but didn’t solve. It smells great, which is a bonus, and is totally safe for us and our pets, which we love. But again, it didn’t eradicate the scorpions from our home. We tried the traps. Again, they work and serve their purpose, but they don’t stop the scorpions from entering, they only help catch them once they’re in. So problem still not solved. We’ve also tried other things: cedar wood blocks and chips everywhere, peppermint and other heavily scented scorpion deterrents, etc. No dice. We really tried to stay away from insecticide, because of how many animals we have, but we were at the very end of our rope. There aren’t many options when it comes to options that can kill scorpions. So this what we went with. We followed the directions and sprayed outside the night we received it. When we woke up the next day, it was like a graveyard out there. Dead bugs everywhere. Not just scorpions, but stick bugs, beetles, stink bugs, June bugs, a variety of spiders (including tarantulas!), mosquitos, crickets, and other things I couldn’t even begin to tell you what they were. Since then, we’ve also sprayed inside, and have found three dead scorpions, three dying scorpions, several new dead scorpions in the traps, and now, about a week in, no scorpions for two days in the house! One I found the first day that was still kicking, I grabbed him with my tweezers and put him in a bowl, then sprayed him. I watched him squirm for about 15 seconds, before he flipped over on his back and died. Just like that. Just stopped, flopped, dead. Also, we run a dog rescue here, and we have 19 dogs. During the day, the dogs are mostly outside in the yard and/or in their outdoor kennels. Since spot spraying and spraying the trees outside, there is a dramatic decrease in the amount of flying insects. >90% decrease in flies, mosquitos, moths, and June bugs. Amazing! So far, no ill effects on us, the dogs, the reptiles (snakes), amphibians (frogs), or small critters outside (bunnies) at all. No impact on the landscaping, no residue or discoloration left on the carpet, walls, or floors. No smell, except maybe a very faint buttery smell when it’s very first sprayed. It’s easy to mix, since the container has the built in measure, and you only need .5-1 ounce per gallon. That’s 16-32 gallons with this 16oz bottle. That’s a great deal for so much peace of mind! This stuff works. It’s safe and easy. Just follow the directions. Don’t over mix it (no need to waste it), make sure to let it dry completely before people or pets touch it, and you’ll be all set.

### ⭐⭐⭐⭐⭐ My personal experience along with an experiment and direct comparison to Harris Scorpion Killer
*by J***H on May 5, 2025*

Scorpion season started earlier this year in South Texas. Ordered this after reading reviews for multiple days and feeling confident that it will help us. Morning started with us finding a scorpion in the laundry room. We caught it in a glass and sprayed one part of the floor with Harris scorpion killer and the other part with Fastcap scorpion killer and waited for both sides to dry. Sat the scorpion on the Harris side and turned the vase over it so it can be controlled on the treated area. Let it run around for about 30 seconds (seemed a reasonable time for it to naturally cross over) and scooped it back into the vase. Watched it for about 2 hrs happily crawling around the vase. No lameness no twitching. Just alive. Time for the second test. This time sat it on the fastcap treated area and again let it run around for 30 seconds. Scooped up and watched it. Here is what happened after exposure: After 2 minutes he got really really slow and we saw right away something is effecting him. After 5 minutes he started acting like a drunk. Uncontrolled body moving, legs kinda tried to crawl in the air and the tail bent over its body. After 10 minutes he flipped on his back and started twitching like crazy. Then nothing. Legs curled up, tail went straight and no movement at all. I moved the lifeless body around in the vase to test any reaction- NOTHING! Watched him for the next 3 hrs. Checked about all 20-40 minutes. At the beginning there was still some slight movement in the legs and pinchers here and there but you could definitely tell it’s just muscle spasms. After 3 hrs I disposed of a dead scorpion. To be fair, he was first exposed to Harris but lived on. Not saying that didn’t somehow affect him but after exposure to fastcap it went very quick. After that I sprayed my entire inside of the house. Under the sinks, behind washer/dryer and along all perimeter of the inside. It’s raining but as soon as the rain will stop I will spray generously outside up the siding and along the base and grass surrounding about 2 feet of the house. My goal is to knock em out the way I saw it happen today before they even get the chance to find an entry point. I’ll probably repeat my experiment with fastcap in about a week to see how the stuff works after some time and will update my review then. For now all I can say is I am happy seeing first hand that it kills these crustaceans fast and am looking forward to report the effectiveness in a couple of days regarding the left over strength HOPEFULLY less scorpion sightings. Before any treatment we found 6 within 7 days.

### ⭐⭐⭐⭐⭐ Best of the Best
*by A***R on August 17, 2025*

Go, buy it now! I’m in a new development in TX with no houses around me yet and the scorpions are out of control. When the new houses start, it will also sent all critters fleeing to my yard. I’ve been using the recommend pest companies and it isn’t adequate. We would still get several scorpions inside each week - even having them come out every 6 weeks. I started using this a few months ago and it’s been extremely effective. I spray for the heavy application- 1 oz per 1 gallon of water with a 3 gallon sprayer. One important aspect of scorpion control is also controlling the pests they eat. This is effective at killing roaches which is one of their primary food sources. No food, less reason to come. I spray the exterior of the house perimeter, flower beds, and 5 feet around my outer property line including 3 feet up my fence. Scorpions are great climbers so you need to cover all areas. We still get the occasional scorpion inside, but it’s usually dead within a couple feet of the door. Scorpions die slowly, so they are difficult to manage. But it’s much better than the daily scorpion that’s lively and fast. I also bought some grabbers to pick them up so I don’t need to handle them. I don’t trust them even once dead… :) I spray every 4 to 6 weeks depending on how much rain we’ve had. TX monsoon rains seem to reduce the effectiveness faster than when it’s dry. As soon as I see grasshoppers or beetles twitching instead of immediately dead I know it’s time to spray again. Good luck and may the odds be ever in your favour.

## Frequently Bought Together

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*Product available on Desertcart Denmark*
*Store origin: DK*
*Last updated: 2026-02-26*