Whiddens' hand-polished Bushing Sizer dies have a shorter overall length for better shoulder bump back, a smaller base and tighter internal tolerances. All of the sizer dies include a shoulder datum collar to measure shoulder bump and headspace. The sizing dies also include a pin retainer should you chose to use the sizer without the expander. Wide knurling on the die make small adjustments simple while the 6-32 machine screw on the lock ring secures the die once the final adjustment is made. The full length bushing die does not include the required bushing. The sizer will accept Redding or L.E. Wilson bushings.