Lyman Accu-Prime Manual Bench Priming Tool Ambidextrous Silver. What makes this tool so accurate is our patented adjustable priming punch (US Patent #11713950). Other priming tools use the top surface of the rim to hold the case during priming and then either use ''feel'' for primer depth or a tool stop of some sort. However even tools with a stop are susceptible to rim thickness variations which will then transfer these variations in primer seating depth. Our patented adjustable priming punch is unique in that the primer cup acts as a stop as it contacts the bottom surface of the cartridge case. In this manner you can precisely control the exact amount of primer depth below the bottom surface of the case. The Accu-Prime also features a smooth working helix camming system to raise and lower the priming punch operated by a unique side lever. Primers are placed into the priming cup by hand and then seated using the 90-degree travel side lever. The tool can be positioned for right- or left-hand operation. Specifications for Lyman Accu-Prime Manual Bench Priming Tool: Manufacturer: Lyman Color: Grey Weight: 2.5 lb Features of Lyman Accu-Prime Manual Bench Priming Tool Works with all brands of standard shellholders Top seating accuracy and precision due to our patented primer punch design Fully controllable and adjustable primer depth Smooth operating side handle with unique helix camming design Accepts standard shellholders Right- or left-hand operation Package Contents: Lyman Accu-Prime Manual Bench Priming Tool Lyman 7770075: Accu-Prime Manual Bench Priming Tool Ambidextrous Silver