Justmysport Bar Locking Collars Barbell Collar Bar Locking Olympic Locking Collars Pair of Locking Quick Release Pair of Locking Barbell Black The bar locking collars can quickly be locked and released. They can help you to improve the safety of your workout conditions. They are perfect for OB47/60/72/86 Olympic bar. They are durable because they are made of high-quality strengthened plastics and ABS.