The Proloc Olympic Barbell Collars are designed to safely hold your Olympic and Bumpers plates secure on most types of Olympic 2″ bars. These collars are lightweight quick and easy to use and very durable. These quality collars are made in the USA out of a high strength molded plastic. The locking pin mechanism distributes the pressure evenly across the bar holding it tight. These collars are a great choice for use on all types of Olympic 2″ bars including various sized bars such as swiss bar econo farmers walk logs rackable cambered bar safety squat yoke bars and solid fat bars. If you are performing Olympic lifts or use these for Crossfit workouts you will like how easy these go on and off and how secure they keep the weights while doing your lifts. So if you are looking for a collar that allows you to quickly make weight changes is lightweight durable and keeps your weights secure on the bar then look no further than the Proloc Olympic Barbell Collars made proudly in the USA.SpecificationsPackaged: 2 collars (1 pair) per pack.Weight: 8.5 ounces per setDimensions (each): 3.5″ H  (4.5 ” including knob) x 2.75″ W x 1.75″ DMaterial: High Strength Molded Plastic with Steel Pressure PinColor: Black MFG Warranty: 2 Years against manufacturers defect from normal use. Knob must not be unscrewed completely.Shipping: UPS Fed Ex USPS