Spike's tactical lowers are american-made to the highest standards.The 7075 t6 forged aluminum has a mil-a-8625f type iii class 2 hard coat anodized finish.This stripped lower is multi-caliber, and low shelf, rdias compatible.The spider model features the st spider logo predominantly on the left side of the magwell.The spider model is the standard lower on all st-15 le rifles.The selector markings on this spider model are bullet pictograms.It has a black finish.Type: Lower ReceiverGun Model: AR PlatformGun Type: AR PlatformCaliber: Multi-CaliberMaterial: 7075 AluminumFinish: Black Hardcoat AnodizedTrigger: None