ProX valve shims are made of premium materials. Specific heat-treatment will ensure hardness of the shims to offer maximum durability and less wear. Next to the specific heat-treatment the shims are precision machined to match exact size. The ProX valve shims are available in complete assortment boxes as well as refill kits. Complete assortment boxes contain a full line of 7.48 mm or 9.48 mm shims for Japanese applications and 8.90 mm and 10.00 mm for KTM applications. Thicknesses range from 1.20 mm up to 3.50 mm. Incremental by 0.025 mm. For most models Japanese Dirt Bikes, Road Bikes and ATV?s and KTM applications, refill kits are available for each individual size and are packed per 5 pcs.