The Tri-Step threaded aluminum insert enables fastening with thermoplastics. It is lead free and has 1/3rd the weight of brass and steel inserts. The insert provides better thread strength than screwing directly into plastic, reduces contact heating time and energy consumption, and requires less insertion travel (typically 3mm for M6). The inserts install by preheating or ultrasonic processes in 1/3rd less time than other inserts. The patented design reduces misalignment during installation and insert spring-back.