Professional A/C Tubing Repair System.Kledge-Lok Aluminum Tube Block-Off A/C Repair, 1/2" (ACR064) Fast, Economical Tube And Hose Repair. â Quick â Easy â Low Cost â No Welding Or Soldering â Airtight And Pressure Resistant â One Tool With Interchangeable Jaws â Large Selection Of Special Connectors And Unions. The Kledge-Lok System Has Been Successfully Tested To 2000 Psi For High-Pressure Applications Such As Transmission Cooler Lines, Steel Fuel Lines, And Oil Cooler Lines.