Check the listing for details. TTC PGB-81 81 Pc Grade B Precision Gage Block Set. Condition: New. Listed at 116.87 USD. Primarily used as reference gages for setting and checking other gages.Features Highest° of accuracy when used at a temperature of 68°F (20°C).Each block serialized, regardless of the grade, for identification when block is re-calibrated and certified at a later date. Alloy steel with Rockwell hardness of 65.Sets are calibrated to meet or exceed federal specifications GGG-G-15C.Grade "B"Supplied with a certificate of accuracy only.Includes(9) Blocks:.1001" to .1009" (.0001" steps), (49) Blocks:.101" to .149 (.001" steps), (19) Blocks:.05" to .95" (.05" steps), (1) Each of blocks:1", 2", 3", 4" PRODUCT SPECIFICATIONSPRODUCT SPECIFICATIONS Brand TTC Grade B Size .1001" thru 4" Includes (9) Blocks:.1001" to .1009" (.0001" steps), (49) Blocks:.101" to .149 (.001" steps), (19) Blocks:.05" to .95" (.05" steps), (1) Each of blocks:1", 2", 3", 4" No. of Pieces 81 Model # PGB-81 Accuracy Grade B Application Primarily used as reference gages for setting and checking other gages. Tool Material Alloy Steel Weight 8.8 lbs. Country of Origin Import