Retay USA ACE Extra Black 20 Gauge 3in Black Semi-Automatic Shotgun - 28in - The Retay Ace Type R receiver is designed with a slight hump back. Featuring a reversible safety button, easily switch from left hand to right hand; stainless steel recoil buffer spring; Airy Pad System softens felt recoil by 30%; drilled and tapped receiver and open loading port. Includes shim kit.