OSO Barbell Collars are manufactured in Columbus, Ohio from the same type of 6061 Billet Aircraft Grade Aluminum alloy used in aircraft construction. The OSO Barbell Collars deliver on functionality, too--creating a secure hold on the bar through repeated, high-impact drops, and allowing easy adjustments or removal with a simple lever and lock/unlock mechanism. All that being said, the first thing a lot of lifters talk about with the OSO Barbell Collars is how they look. Shaped like an industrial gear, the collars' old school design is paired with some bright color options: blue, green, orange, pink, purple, red, gold and gun metal. For Oly lifters, CrossFitters, or any athlete looking for an upgrade from basic spring collars, OSO Barbell Collars are a nice option. Specifications: Sold in Pairs Made in the USA Designed to be used on 50MM Olympic Bar Sleeves 6061 Billet Aircraft Grade Aluminum Weight: 0.8LB per pair Width: 1.5" Orange Rubberized interior lining to protect bar Locking clamp mechanism for secure hold