5 out of 5
Customer Reviews
By
4Lincoln
Date: December 05, 2025
This is a very high quality tool for use by professionals. Very easy to use. Those that complain about the wrong fittings simply bought the wrong one. This one is for R134a, Mastercool also offers one for use with R12 systems. The fittings are different. You do have to inspect and clean out the barrel prior to first use. This injector may be used before charging a system or with a fully charged system. I own all of the Mastercool line of A/C service tools. They are the highest quality and the highest value. Don't trash this fine tool because you are not a professional and don't know how to use it.
Rating: 
[5 of 5 Stars!]
[5 of 5 Stars!]
By
James L. Lamping
Date: November 23, 2025
A must for injecting liquids into an auto ac system. Very easy to use.
Rating: 
[3 of 5 Stars!]
[3 of 5 Stars!]
By
Dennis76nyc
Date: November 14, 2025
I just wished it had a bigger oil capacity.
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
Robert C.
Date: October 05, 2024
I'll let you know how it's.
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
impala572
Date: September 22, 2024
GREAT
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
MARK K.
Date: August 27, 2024
new stuff
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
Lee Kissinger
Date: August 09, 2024
As promised, quick delivery great value
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
Vlady
Date: July 23, 2024
exelente
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
Waddie
Date: July 19, 2024
Very good quality. The valve works and is also of high quality. The body is machined, the threads are clean. I had no trouble using this item on several auto AC systems this summer. I would recommend it to anyone who needs a way to get oil into their AC system. On one car when I didn't have my gauges with me I just used a can of 134a to push the oil into the system. Worked perfectly that way.
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
A Customer
Date: June 29, 2024
Great product great price. Very happy
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
Compucarracing
Date: June 21, 2024
Worked Great, Great Deal!
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
Arthur T. Pierce Jr.
Date: June 18, 2024
Its alot of effort but it works as advertised. You have to use in conjunction with a evacuation pump.
Rating: [3 of 5 Stars!]
[3 of 5 Stars!]
By
Nigel
Date: June 03, 2024
I used this to add oil back into my Ranger's AC system. I wasn't sure if I was doing it properly as per their instructions and I had to pull a vacuum a couple times to get all 2oz of oil into the system but other than that it worked fine. Very solid piece. MAKE SURE YOU CLEAN THIS BEFORE USING!!! Can't stress that enough. I ran some brake clean through it and emptied the contents on a towel. I saw MANY metal shavings of aluminum and casting oil (black stuff). I am glad I read a review stating to clean it first or I would have just used it and gotten that crap into my system. I'm putting it in my review as well to hopefully help someone as well. I had no issues getting the cap on or off. Threads were clean and all fittings/orings were sound.
Rating: 
[4 of 5 Stars!]
[4 of 5 Stars!]
By
bvf_aries
Date: April 29, 2024
Works as expected.
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
Pat
Date: March 19, 2024
works great
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
Dan F
Date: October 13, 2023
These are a must have when charging a system. If you can't figure out why the gas leaked out and it holds vacuum fine, you need to put dye in the system to figure out where the leak is (and hopefully it leaks in a place where you can actually see it.)
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
Clifton Pilgrim
Date: August 13, 2023
Allows me to do it the right way
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
Michael D. Butler
Date: August 09, 2023
Excellent quality AC service tool.
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
mayvill
Date: June 09, 2023
excelente
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]
By
Jon M.
Date: April 12, 2023
Great product very well constructed. Easy to fill and use.
Rating: [5 of 5 Stars!]
[5 of 5 Stars!]