EG02-0411: Precision 1-2-3 Blocks 2 Pcs/Set, Precision ground and case hardened on all sides; Squareness of all sides is sides is within .0001" per inch; .0001" To .0003" over allowance for nominal lapping; Five 3/8-16 tapped holes provided for clamping operations
EG05-3050: Sides are parallel and vee is central and ground; central hole is provided for drilling or removing pins; V-block has (4) 3/8"16 tapped holes, (2) in the base and (1) on each side for angle iron clamping; Block is provided with black oxidized clamp; Parallelism tolerance of Vee axis to base within 0.0003"/8 microns