Ball Bearing "V" Block overcomes Production or Set-up difficulties inherent in plain V-Blocks. Overcomes geometric limitations. Enables you to inspect and detect out-of-round conditions and lobes With no damage to parts and no damage to Blocks. Special Features: Accuracy of Balls: 25 Millionth of an inch sphericity on small and medium Set. 50 Millionths of an inch on Large Set. Overall Accuracy of Matched pairs +/-5 Microns. Balls Rockwell C-62 - surface Finish 0.2 Microinches. Calibrated Balls are certified. Class 40 Cast iron, used on Base and housing, is heat stabilized and seasoned. Spacers are Hardened through and Precision ground by pairs. pair of Blocks assembled using metrology equipment. Available in 3 Sizes With Ranges of: 3/64"-2 1/2"; 3/32"-5"; 3/16"-10" and up. Sold in Matched pairs complete With Clamps(for use when machining). Special Functions: Balls undergo slight elastic deformation when parts are loaded on. Hence parts will not be damaged while being inspected or Produced. Detection of lobes and Superimposed lobes Made easy. Easy readjustment of Balls which Provide new bearing Points. Handles Diameters up to 15 inches. increased contact area due to special geometric spacing of Balls in Blocks. 8 contact Points per pair of Blocks share load distribution. Balls are self-aligning and Hard wearing. 1 each Precision Spacer per Block Provides 2 different Angles per pair. Simply turn each Block 90° and inspect component using both Angles. Special inspectionSet ups using Cylinder Squares now possible. Important Note: Balls are fixed in Blocks and are not designed to rotate in use. Model No. 16095, V-Blocks, 4 3/4" X 4 3/4" X 2 3/8" Complete With Clamps and Test Ball.