





🛠️ Master every valve core job with precision and portability!
The Mastercool 81290 is a compact, dual-ended valve core remover and installer designed for R12 and R134a systems. Featuring hardened steel shafts compatible with Standard, JRA, and Eaton large bore valve cores, this durable tool enables fast, pressure-free servicing. Its pocket-sized design makes it an essential, reliable companion for HVAC professionals handling system recovery, repair, or retrofit.



| Manufacturer | Mastercool |
| Brand | Mastercool |
| Model | 81291 |
| Item Weight | 0.8 ounces |
| Product Dimensions | 2.4 x 2.3 x 1.1 inches |
| Item model number | Standard/JRA/Eaton – R12/R134a |
| Is Discontinued By Manufacturer | No |
| Manufacturer Part Number | 81290 |
| Special Features | All Purpose |
| National Stock Number | 5120-01-592-4515 |
M**S
It works great like it should
The media could not be loaded. It worked out great to help replace my Ac low side schrader valve on my 01 Tahoe which is the main cause of lost ac Freon on these trucks that I have seen. It’s a good size to help with tightening and loosening, and not loosing it as well like my previous one. It has 2 different sizes to fit other valves which is nice.
J**T
A great tool to have around
I noticed a leak in my car's AC low side connection. I ordered the tool and got it the next day. It took about 30 seconds to reseat the schrader valve. God only knows how many $$$ a repair shop would have charged.
B**N
One quality tool is worth one hundred low quality tools
After fighting with this valve for 2 days I finally got this tool in the mail. As you can see the valve had been completely tore up by lesser quality valve tools that either broke off or stripped out when force was applied.I put this tool on, tapped it with a mallet to seat it on the valve, and used a pair of pliers to turn it. It saved me from having to run a new ac line or have a shop do it for hundreds of dollars! It’s great quality and appears it will hold up to just about anything. Worth the xtra premium
J**.
size handles regular and 670
ruff shape.
K**S
Works as it should
The mastercool schrader valve tool is very sturdy and does the job it was intended to do.
M**E
It was the tool for the 07 ranger
worked FoRd tough.
R**E
Worked without breaking
I bought this because another one I bought with a valve kit broke off, cheap steel I guess. This one is strong.
P**S
Mastercool
The master cool (81290) for R134aworked perfect.It has two sizes for the ac shrader valve,a small size on one end, and a large size on the other, end and it isfixed in the middle to get a good grip on it.At a very good price. I would surely recommend the master cool. (81290) For 134a
Trustpilot
2 days ago
4 days ago