1/8 X 3 in. Precision Parallel Set & 1-2-3 Matched Pair Block Set

HHIP 1/8 X 3 in. Precision Parallel Set & 1-2-3 Matched Pair Block Set The 2-hole parallels are made from fine quality tool steel that is stress relieved against distortion. These parallels are precision ground and hardened and are complete with a fitted wood case. Sizes include 1/8 X 1/2 X 3 in., 1/8 X 5/8 X 3 in., 1/8 X 3/4 X 3 in., 1/8 X 7/8 X 3 in., 1/8 X 1 X 3 in., 1/8 X 1-1/8 X 3 in., 1/8 X 1-1/4 X 3 in., 1/8 X 1-3/8 X 3 in., 1/8 X 1-1/2 X 3 in. and 1/8 X 1-5/8 X 3 in.. The tolerance for the parallels is parallel to 0.0003 on 2 sides, top & bottom and the dimensions are within 0.001 in. allowance. The 23 hole 1-2-3 blocks are heat treated and case hardened to HRC 55 to 60 and are hardened and precision ground on all 6 sides of each block. These blocks are accurate with squareness on all sides within .0002 in. per inch. The 23 holes consist of 5 tapped holes that are 3/8 in.-16 for clamping and 18 untapped holes. The 1-2-3 blocks have a cross drilling design to give them minimum weight and maximum strength.