Feature: Heat-Set is designed specifically for notch-sensitive plastics Expansion-Sets offer simple press-in installation Flow-Sert is a blind insert for installation during the moulding process Brass Material Can Resist Heat. Not Easy to Rust, Strong Corrosion Resistance. Very high pull-out and torque resistance. Can be installed by ultrasonic or Heat into thread tapered hole, or moulded in during injection. No need to counterbore or countersink the boss hole since the insert has guide pilot. Used on the injection moulding for tightly fixing.