This precision ground clamping V-block is crafted to maximize the accuracy of just about any setup for grinding and milling. It is supplied with 3 3/8"-16 threaded holes so you can easily mount it to fixtures, jig plates or angle plates and hold round stock up to 1-1/4" in the horizontal or vertical positions. Hardened better than 45 on the Rockwell hardness scale for durability. Stirrup is supplied with adjustable clamp stop. Measures 3-5/8" x 1-7/8" x 1-7/8"