Made in U.S.A

Hex heads are manufactured by Robbins Mfg. Co. and nuts by Robbins Mfg. Co., Texas Bolt Co., and SPS-Non-ferrous. All hex heads are made of 304 stainless steel. Heads are marked with Robbins "R" trademark and "B8". Finished and heavy nuts are made to ASTM A194 specifications and stamped with manufacturer's trademark and "8" or "8M". Some finished nuts are also stamped "304" or "316".

Chemicals and physicals available showing compliance to ASTM specifications.
  • Material to ASTM A193 grade B8 specification and to ASTM A194 grade 8/8M specification.
  • Dimensions on ANSI/ASME B18.2.2, threads to ANSI/ASME B1.1.
  • Manufacturing process, mechanical properties, hardness, and marking to ASTM A193 and ASTM A194.
  • Testing to ASTM A370 specification.
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Unit of Measure
Items
1224_heavy-nuts

Grade 8, 8M 316 Finished Nut, 1/4-20
1224_heavy-nuts

Grade 8, 8M 316 Finished Nut, 5/16-18
1224_heavy-nuts

Grade 8, 8M 316 Finished Nut, 3/8-16
1224_heavy-nuts

Grade 8, 8M 316 Finished Nut, 7-16-14
1224_heavy-nuts

Grade 8, 8M 316 Finished Nut, 1/2-13
Manufacturer N/A Robbins Manufacturing Co., Inc.
Product N/A Nuts
Codes and Standards N/A ASTM A194 Grade 8, 8M
Thread Size N/A 1/4-20 N/A 5/16-18 N/A 3/8-16 N/A 7/16-14 N/A 1/2-13
Type N/A Finished
Stamping N/A 304 316 N/A 304 316 N/A 304 316 N/A 304 N/A 304 316
Material N/A 304 Stainless Steel
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