The Hornady zip spindle kit is the ideal kit for updating your older Hornady sizing dies to utilize the new threaded spindle design. The zip spindle design on all full length size dies positively locks to eliminate slippage. A Series of light threads cut on both the spindle and spindle collet allows you to make incremental adjustments by turning the spindle or you can easily zip it up or down for larger movements. includes a new threaded spindle and a threaded spindle collet. Fits: Any Caliber Hornady New Dimension Sizer Dies (except 17 and 20 Caliber)