1. Specify Shape, signified by the following symbols: 2. Specify Material (croblox® , steel, or ceramic) 3. Specify Unit of Measure (inch or metric) 4. Specify the Size 5. Specify Special Lengths, if applicable (Rectangular Only) • Thin block sets (28 pc. inch and 17 pc. metric) are all 1.115" (28.3mm) long. Specify "SS" length. • .050", .100", and .150" blocks in inch 81-92 pc. sets are 1.380" long. Specify the Long length, "L". • .100" blocks contained in the 36, 38, and 43 pc. sets are 1.380" long. Specify the Long length, "L". 6. Specify Accuracy Grade (see next page) 7. Specify if you require a Commercial, Master or Laboratory Calibration*. See the catalog page regarding our Accredited Gage Block Calibration Service near the end of this section. A certificate of calibration provides individual readings on each block and provides traceability to NIST. Webber gage block calibrations are NVLAP® accredited by NIST. (We require the end user's name and address to place on the certificate.) * Commercial calibrations are included in the price of gage blocks. Master calibrations are done at extra cost. Laboratory calibrations are done at extra cost and are restricted to Webber croblox® rectangular style gage blocks of grades LM, AA, GGG grades 0.5 and 1, and B89 Grades 00 and K. 8. Specify if you require special etched serial numbers. We can provide up to a 6-digit maximum. If an etched serial number is not specified, we will assign a number that is a coded date. Individual Gage Blocks Gage Block Sets 1.  Order by catalog number. 2.  Please specify if you require a Commercial Calibration or Master Calibration. See the catalog page regarding our Accredited Gage Block Calibration Service near the end of this section.A certificate of calibration provides individual readings on each block and provides traceability to NIST. Webber gage block calibrations are NVLAP® accredited by NIST. (We require the end user's name and address to place on the certificate.) 3.  Specify if you require special etched serial numbers. We can provide numbers up to a 6-digit maximum. (Our standard practice is to put the same etch number on each block in a set. Blocks are differentiated by their marked size.) If an etched serial number is not specified, we will assign a number that is a coded date. The buyer ofWebber products listed in this catalog agrees to the 100% Relaxed Acceptance Rule contained in ASME B89.7.3.1 (Guidelines for Decision Rules:  Considering Measurement Uncertainty in Determining Conformance to Specifications). Products may not be rejected by the purchaser unless his measurements exceed the published tolerances by more than his uncertainty of measurement. NVLAP® accreditation does not constitute an endorsement of any product by NVLAP® or any agency of the U.S. government. How To Order St arrett Precision Gage Blocks NVLAP LAB CODE 200038-0 National Institute of Standards and Technology National Voluntary Laboratory Accreditation Program St arrett-Webber Gage Division 24500 Detroit Road Cleveland, OH 44145 Phone: 440-835-0001 Fax: 440-892-9555 E-mail: sales@starrett-webber.com DIMENSIONAL NVLAP Code: 20/DO3 Gage Blocks • Rectangular • Square • Heavy Duty 377 starrett.com S t arrett -W ebber G age B locks