Features: Feature: Come with Anti-Vibration tension ring, can resists vibration leaks. Compensates for out of bounds or scratched tubing. Expanded seal sleeve provides more sealing area. This set includes 3 different sizes(3/8", 1/2", 5/8"). Made of high-quality aluminum, with excellent corrosion and rust resistance. Function: Works for A/C, coolant, heater, oil, P/S return, and trans line repairs. It helps to restore the air conditioner to its original operating temperature and prevent future failures.Can quick, durable permanent metal line repair without line removal and No crimping tool required. Repair only the damaged part, not the entire A/C circuit assembly, Complete your repair in minutes. .