Spring-style collars and quick-lock/quick-release collars are the fastest to put on and take off. Variants use quick-release levers, snap latches, or quick-lock mechanisms to speed plate changes.
Most collars and quick-lock clamps in this group are made to fit 2-inch (Olympic-style) bars and common curl/super-curl bars.
Clamps are made from various steels (cast iron, carbon steel, spring steel often with a chrome finish), aluminum, and molded/resin or plastic materials. Many also include protective rubber or non-slip linings.
J-cups are designed for rack use: they attach to power racks or half racks to hold the bar, protect knurling, and provide a secure lift-off point.
Many collar-style clamps are designed for quick installation and removal. Common features include quick-release levers, quick-lock mechanisms, snap latches, and one-button unlocks for fast plate changes.
