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Stainless Steel Hex Bolt Grading

Hi,

I've acquired about 1000 lbs. of 1 1/8" diameter x 4" stainless steel hex bolts, nuts and flat washers. I'm familiar with standard steel bolt markings for grade 5 & grade 8. These bolts have an "S" in the center with 2 hash marks, one pointing to 12:00 and one pointing to 3:00. I would appreciate an explanation of these marks.

Thank you,

Herb Moore
- Middletown, Pennsylvania
2002

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Herb, you might take a look at MIL-HDBK-57B, "LISTING OF FASTENER MANUFACTURERS'IDENTIFICATION SYMBOLS". It is available at the ASSIST website, like all the other military specifications. With a quick glance, I don't see the symbol you described, but perhaps a closer inspection will find it.

Good luck!
Lee Gearhart
metallurgist - E. Aurora, New York
2002

I found your answer at Viking Bolt while looking for my answer. It is an 18-8 "300" series LOW GRADE.

Tracy Ziola
- Shohola, Pennsylvania
2002