Worx WA3578 - PowerShare 20V 4.0Ah, Lithium Ion High Capacity Battery, Orange and Black

Great battery, just as good or better than originals (seems to last a tad longer). Fits my Worx weed eater and leaf blower, think model 155 or 151 - the combo deal Lowes offered back in 2014. I have bought two of these batteries now (product came with one) so have enough power to weed eat entire property all at once (about an acre). The trick to these batteries in getting long run time out of them: (1) let them cool off before recharging; (2) give them a quick charge the night before you are going to be using them (they lose a bit just sitting), and (3) ensure you have NOTHING like tall grass, string, and the like wrapped around the shaft under where the twine goes in. It seems like if the shaft has clutter wrapped around it, the battery has to work harder to try and spin, thus draining the battery much faster. Personally, all of my batteries (all this battery) last about 2 hours if the shaft is clean, and I give them a quick boost the night before using them. The gazillion dollar question that I personally cannot seem to answer or get an answer for is how to get the blasted cutting head off the weed eater in order to EASILY clean all debri from the shaft!!! NO, it is not in the owners manual. NO it is nowhere on the Worx website. NO it is not on the web or on any of the fix it answer sites - they have no clue and all think this is a gas weed eater. There is NO allen wrench nut anywhere. There is a teensy screw under the orange cap, but I can't figure out why its even there (removing it does not do anything). The people at Lowes have no clue (where I bought it from). There is an unusual looking type of reverse pattern socket hole under the cap that I kinda feel might be the answer, but no hardware store I've been to (took the weed eater with me, showed them) has a clue as to what tool might fit in there, and if that reverse pattern socket hole even has anything to do with taking the cutting head off to get to the shaft. The only solution I've come up with is to patiently use needle-nose plyers and sit for about an hour and turn the spool the opposite direction, grabbing pieces of grass/weeds wrapped around the shaft, and gently pulling them out until I can start to see the shaft itself. I know full well I'm not getting it all, but if can get most of it out, the weed eater runs much longer the next time need to use it. Any other owners of this weed eater - if you have the answer I seek, I'd be greatly appreciative of your assistance!!! Totally recommend this product at this price; it's worth having a spare and the price is fair, and these batteries are hard to find in stores at a reasonable price (if you can find one at all). NO, I am not a paid reviewer, I have no incentive to post this review other than to help other real live purchasing Amazon customers make an informed decision. Personally, I detest what Amazon is allowing to happen with the starred ratings becoming "skewed" by years and years of reviewers that have been given a product free of charge in return for an "honest" review. My review is based on my personal use of this product, and I'm taking time out of my busy schedule to try and balance the scales a bit in my own little way by helping out other real live purchasers know a TRULY GOOD product and a GOOD BUY when they read my review.

The 4A WA3578 battery is just what the doctor ordered for my Worx tiny chainsaw. It came with a 2A battery: OK for very small jobs but ran out of juice after about half an hour of cutting and dragging away fallen branches. With a lot of tree damage last winter half hour barely made a dent before hours of charging (slow charger that came with my saw). With the addition of this 4A battery I keep going for an hour and a half before I have to start recharging again. By then I'm happy to take a break. EXCELLENT! It is (no surprise) about twice as heavy as the 2A battery, but Worx did a good job with my little chain saw. Even with the battery it maintains good balance. Nice design. I thought about going with a 3rd party 4A battery, but decided to stick with the brand name. Just want it to be dependable and compatible Even with my slow charger this 4A battery has exceeded my expectations. I'm giving a hearty 5 stars.

I have a Worx string trimmer that came with a 2AH battery. That original battery always ran out about 80% through using it. This 4AH battery easily lasts the entire job, and I still have the 2AH one in reserve. It seems to be a pretty well-made pack, and the cells inside are hopefully quality and long-lifetime. It was pretty expensive, but that's the way these power tool companies work now. Cheap tools, expensive batteries. SPECIAL NOTE: I tried a cheap "6AH" Chinese knock-off no-name battery before I bought the name-brand one, and it wouldn't even charge with the official charger. When I took it apart and tested the 18650 batteries inside the knockoff Chinese battery, they corresponded to an overall battery pack that had about 2.5AH (not 6AH), so even if it had worked, it wouldn't have been worth the price, as it was about the price of a 2 or 3AH battery. Also, the reason it wouldn't charge was that the battery management system board was dead on arrival. Long story short, I do NOT recommend buying the knockoffs. They overstate their capacity, they use mediocre cells, the electronics in them are cheap and unreliable, and they are probably dangerous as a result. If you are strapped for cash, you might as well just buy the name-brand in a "lower" capacity.

Well unlike the knockoff brands it holds it's charge very well,does a very good job.

Save yourself some money. Cost less than buying at big box stores!

And ready to store more for your convenient use. I have about decided that this battery is about all the work I want to do with a WORX tool - in this case a chainsaw. By the time this battery gives out, so am I and it's time to quit anyway. Since they have a variety of battery capacities, base the size you buy (2A, 4A, 6A, etc.) on your age and the amount of time you want to work. That way, when you flop out in the easy chair after a round of yardwork you can tell the wife "I worked until the battery ran out.... it's recharging!" and you can recharge with cold adult beverage with a true metric to judge your work by. Inescapable logic! Just don't let you wife be ordering any extra batteries or that high speed charger thingy they sell. If you convert all your yard equipment over to WORX you can even use it as a bargaining tool! "Honey, I'm gona weedeat the yard until the battery runs out, then I have to call it....." You can tell your buddies at 1:00pm, "Hey, I gotta weedeat the yard first and the battery lasts about 45 minutes, so I can make that 2:00 pm tee time!" Thanx Worx!

Lasts for almost an hour with my Worx chainsaw. Charges pretty fast and has unstoppable power.

I needed another battery for my leaf blower so I bought another battery that is the exact same as what was supplied with my Worx device. This battery is great. Works just the same and holds a long charge. Easy to use with my charger too. My only complaint is it's a bit pricey for just a 20V battery.