Is your air conditioner leaking? Not to worry; 4Lifetimes' 3/8" Ferrule AC Repair has you covered! This compression-style tube repair is a quick, economical way to fixing pinhole leaks, cracks, kinks and rub throughs in air conditioning, coolant, transmission, oil or fuel lines. You'll save time and money with this permanent leak repair by using standard hand tools on steel, aluminum or copper applications -- straight or reducing. Note: not suitable for brake or clutch systems.