Roepke Olympic Clamp Collars are clamp collars with a compression lever constructed from solid aluminum for use in securing weight plates onto an Olympic barbell, such as a hex bar or trap bar. They are simple, fast, reliable, and durable. The solid extruded aluminum structure of the Roepke bar clamps is not only rust resistant but also offers all the strength without the weight or bulk of traditional steel or iron collars. The design of the collar is very slim, taking up only one inch of space on a bar sleeve. Unlike many clamping collars which take up 2 to 2-1/2 inches of space, the Roepke collars allow more room for "heavy loading" especially when using thicker bumper plates for controlled movements. They are designed for non-impact or low-impact strength training movements such as squats, bench press, deadlifts, upright rows, shrugs, curls, and other heavy duty training exercises where weight plate stability and security is desired for peace of mind and safety. Minimalist in size and weighing only a pound total for the pair, these virtually indestructible compression collars make a great addition to your gym bag training arsenal.