RCBS's Caliber Pilot/Neck Reamer are two tools perfect for fast, easy removal of excessive neck thickness or variation in neck thickness. The pilot reamer supports the cutter as it is guided over the sized cartridge case neck. The auto feed attachment works with the RCBS Case Trimmer 2 and the RCBS Trim Pro to advance the cutting tool over the case neck with each turn of the trimmer handle. Not to be used with the Trim Pro Power Case Trimmer. All RCBS reloading equipment is made in the U.S. and 100% reliable.