Pins fail to reach Schrader valves on 50% of vehicles. I had the same problem with other cheap plugs that came with my gauges. I recommend buying Robinair clutches.
Enhanced Elitech ILD-300 Infrared Refrigerant Leak Detector: Advanced HVAC Halogen Tester with Selectable Gas Functionality
9 Review
Lichamp Automotive R1234YF Installer Standard
9 Review
π¨ Robinair (15115) VacuMaster Single Stage Vacuum Pump - For Efficient Single-Stage Vacuuming, Delivers 1.5 CFM
9 Review
Robust Robinair (RG3) Portable Refrigerant Recovery Machine, 115V, 60Hz -Efficiently Recovers Liquid and Vapor Refrigerant
9 Review