PER: IIW & USAF T.O. 33B-1-1 (6-1-84)
Modified version of Type 1 with a 2″ radius 1/4″ deep cutout test side for time based distance calibration and three extra side drilled holes which permit sensitivity level setting.
Case Not Included
Blocks are precision manufactured to tolerances well within the allowable limits of their respective codes. All blocks pass a comprehensive quality control inspection in accordance with ISO 9002 (formerly MIL I 45208 A), with instruments calibrated in accordance with ANSI/NCSL Z540 (formerly MIL C 45662A). All calibration blocks are serialized and certified to the National Institute of Standards and Technology.