These barbell collars are designed to fit standard-sized bars that measure 2 inches in diameter. Unlike typical steel collars that need to be screwed for attachment, these barbell collars clamp down tightly on the bar with just a press of the latch and quick to remove and put on. You're no longer wasting energy between sets futzing around with spring style collars. The barbell clips 2inch are fit for locking Olympic bar and quick release and soft elastomer pads for a secure grip. Great holding power during working out.