The Sinclair Reloading Die Shim Kits allows you to make fine adjustments to your reloading dies quickly and easily while still being able to return to your original setting. Each shim is notched for easy size identification. Just set your die using one of the middle thickness shims, adjustments can be made easily by changing shims to increase or decrease die depth without changing the stem setting. A great upgrade to non-micrometer adjustable dies. 7/8-14 Shim Kit includes 7 Shims of varying thickness and are best used with Sizing Dies Arbor Die Shim Kits include 10 shims of varying thickness and best used with L.E. Wilson Seating Dies. Mfg: Sinclair International