Battle Arms Development QD Sling Mount, Fits M-LOK Rail System, Black BAD-MLOK-QD The Battle Arms Development M-LOK QD Sling Mount provides an attachment point for a quick detach sling on a M-LOK handguard. It allows the user to customize where their sling will be attached for optimum comfort and operation. Rounded edges reduce the chances of snags or hang-ups. All required mounting hardware is included. Battle Arms Development" Inc. (B.A.D. Inc.) is a design" research" and development firm incorporated in 2009 with a focus on small arms design including firearm components" tools" gauges" accessories" and complete weapon systems.