7PCS Pressing Jaws: press jaws set includes 7 jaw sizes: 1/4', 3/8', 1/2', 5/8', 3/4', 7/8', 1-1/8'. Compatible with standard electric press tools (PZ-1550, PZ-3240, EB-1550 Model) and other brands (CT-400, RP310, RP310PLUS, RP318, RP320-E, RP330-B, RP330-C, RP340, RP350, RP351, M18 Model) Applicable Material: Our pressing jaw is compatible with RLS copper piping, providing a reliable and efficient solution for pressing fittings in high pressure HVAC/R applications and various piping applications 10,000+ Perfect Crimps: Crafted from high-strength carburized steel with a hardness of 52HRC, these crimping jaws ensure precise control over applied pressure and torque, ensuring high-quality connections and sealing performance Easy to Carry: Compact and lightweight, this pressing jaw is also ideal for use in confined or tight workspaces