Adjusting shoulder bump has never been easier. The Whidden Gunworks Click Adjustable Bushing Full Length Sizer Die and lock ring work together to give the user a clicking feel to the adjustment just like a high end rifle scope. Each click moves the shoulder bump .001" so you can easily find the exact shoulder bump that you desire. Included with the Click Adjustable Sizer Die Set is a Micrometer Adjustable Seating die and Shoulder Bump Gauge. This gauge attaches to standard calipers and allows measurement from the case shoulder to the base. Mfg: Whidden Gunworks