ET Arms Inc Lower Parts Kit Includes Pistol Grip, Fire Controls, Springs, Pins, Detents & All Necessary Parts For AR-15 Lower, Nano Composite This lower parts kit from ET Arms is made 100% durable nano composite technology and steel parts that fits and will complete your AR-15. Kit Includes: Pistol Grip, fire controls, springs, pins, detents, and all necessary parts for the AR-15 lower.