Phase 5 Weapon Systems Sloped Quick Disconnect End Plate, Black Finish SQD-EP The Phase 5 Sloped Quick Disconnect End Plate (SQD-EP) was designed to replace the standard AR15/M4 carbine end plate. While still meeting the requirements of the original design" the SQD-EP is lighter and QD Swivel compatible. The QD mount is at a 30 Degree angle from the lower receiver to allow a 360 Degree rotation for ambidextrous use.