How to Identify Grade 5 Nuts & Bolts
- 1). Pick up the bolt and look at the hex end. The hex end is the end on which you place the wrench.
- 2). Count the number of slashes on the top of the bolt. A grade 5 bolt will have three slashes radiating out from the center in a "Y" formation.
- 3). Pick up the nut. A grade 5 nut will have a raised or depressed insignia identifying the manufacturer. There will also be three small dashes radiating out from the perimeter.
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