Increases the range of Inch reading 258 DIGI-CHEK™ Height Gages by 10". Heavily flanged for rigidity and stability. Both top and base have three ground and lapped pads to match the pads on the DIGI-CHEK™ base. Retaining plate prevents the DIGI-CHEK™ from being pushed or sliding off the pads. Attractive black wrinkle finish. If desired, riser blocks can be stacked one on top of another.