Review on Wisepick Injector R 134A Quick Coupler by Phillip Brown

Bottom line, it works. The collar was not attached so I swapped it out for a collar with a pressure gauge. Apart from this error, the item worked fine. My personal recommendation is to fill up to 1.5 or 1.75 ounces as much as possible. 2 ounces kept the piston from pushing and the threads from engaging. This thing saved me the heartache of having already drained and recharged my system only to find I hadn't added enough oil.