Worlds Finest Trimmer 2 Trim Chamber Trim Chamber for use with the WFT2  World's Finest Trimmer 2 Housing/Cutter Assembly sold separately Each chamber is designed for a specific cartridge or cartridge family such as a 308 trimmer will also trim 7mm-08, 260 Rem., 243 Win. Does not use pilots, the case is supported by the shoulder and case body