HHIP 2-1/2 INCH SINE BAR (3402-1203) 2-1/2" (L) x 1" (W) Working face accuracy 0.00003"/ per inch. | Rolls center distance accuracy 0.0002". For angles set up by using Sine Bar with 1-2-3 Blocks or Gage Block. Parallelism: 0.0004". Flange on the end for the resting of workpiece.