This adapter is to be used to attach the ACC-004 Objective Flip Cover and designed to work with the 4x32 BROWE Combat Optic, 4x32 BROWE Tactical Optic, or 4x32 BROWE Sport Optic. To Objective flip cover (ACC-003) requires either ACC-008 adapter or the ACC-002 Tenebraex Killflash ARD.