Croc Lock™ CollarCroc Lock Collar *Patent Pending The Croc Lock Collar works. It's built like a tank. It has a million uses and this is all just the start. If you've been around big time strength training for a while, and train in a powerlifting gym, you know somewhere in the gym is a bucket or a tool drawer filled with broken "specialty bar" collars. Ones that got in the way after you missed that last attempt or ones that got trapped between the weight in the floor.