columpro hvac repairing tools, air conditioner copper pipe expander swaging tool, 1/4 inch hex shank copper pipe flaring tool tube expander,1/4''， 3/8''，1/2''， 5/8''，3/4''，7/8''bits - ✅【Superior material】 Made of 40CR ball bearing steel，Durable, heat-resistant and wear-resistant, not easy to break, use it with confidence and safety.. in the past
