The magnetic attachment system gives instant fitting and has an adjustable lever system for extra security. Lightweight and durable the Heavy Duty Optics Adapter comes with a standard 1/4-20 camera/optic screw 3/8-16 bushing and polymer plate. – Turns your APEX MagnaSwitch Head into a super stable optics and camera platform in seconds – Designed to attach to cameras and other optics with standard 3/8-16 or 1/4-20 threaded female mounting points