The ELF Service Trigger has been built for law enforcement and military duty. This trigger has an adjustable pull weight between 4 lbs and 7 lbs. The only AR-15 trigger using aerospace grade sealed bearings, making for an incredibly smooth and fast trigger pull. Our exclusive .043 double double wound polished piano wire hammer spring ensures full ignition of any ammo including .308 and 7.62x39. Pull weight from 4lbs to 7lbs is so easy to adjust it can be done in seconds without removing the trigger from your lower receiver. A second-to-none AR-15 drop-in trigger system that is strong and light, made of wire EDM machined, hardened A2 tool steel and lightweight aircraft-grade aluminum. Inst Mfg: Elftmann