3/8"-16 x 5-1/2" Grade 8 Bolts (10-Pack) – Heavy-Duty Hex Bolts Includes Flat Washers Lock Washers & Nuts – High-Strength SAE 5.5" Coarse Bolts for Automotive, Machinery & Construction
Product details
| Management number | 211256809 | Release Date | 2026/04/04 | List Price | US$13.10 | Model Number | 211256809 | ||
|---|---|---|---|---|---|---|---|---|---|
| Category | |||||||||
These 3/8"-16 x 5-1/2" (5.5") long Grade 8 (G8) Bolts are engineered for applications where strength, reliability, and vibration resistance matter most. Each pack combines a high-strength Grade 8 (G8) hex bolt, a matching hex nut, two flat washers for load distribution, and a lock washer to maintain torque in demanding environments. Designed for use in automotive repairs, trailer builds, agricultural equipment, shop machinery, and structural assemblies, this kit eliminates the need to source parts separately—saving time while ensuring proper fit and performance. Whether you’re a professional mechanic, fabricator, or serious DIYer, this fastener kit delivers the confidence of industrial-grade hardware in a convenient, ready-to-use package.
- Complete 10-packs: Includes 10 Grade 8 hex bolts, 20 hardened flat washers, 10 hardened split lock washers, 10 hex nuts — everything you need for strong, vibration-resistant fastening in one convenient pack. Bolts 3/8" x 5.5" long. Nuts and washers fit 3/8" bolts.
- Grade 8 Strength for Demanding Jobs: High-tensile SAE J429 Grade 8 bolts and nuts deliver superior load capacity and shear strength, making this kit ideal for automotive, trailer, machinery, and structural applications. All washers are hardened, which is compatible with a Grade 8 fastening system. Threads are made to the requirements of ASME B1.1. ASME B18.2.1 Dimensional Requirements. SAE J429 Material and Strength Level. ASTM A564 Material and Strength Level. ASTM F788 Surface Discontinuities. ASME B18.18 Inspection and Quality Assurance.
- Vibration-Resistant Locking System: washers help prevent loosening under torque, shock, and movement — perfect for equipment that sees constant vibration or cyclic loads.
- Precision-Matched Components: All fasteners are 3/8"-16 UNC for reliable fit and consistent clamping force across every assembly — no mismatched hardware, no guesswork.
- Built for Pros & Serious DIYers: Whether you’re repairing equipment, building fixtures, or assembling heavy components, this kit delivers industrial-grade reliability in a compact, easy-to-store format.
| Brand | Quantum Forge |
|---|---|
| Color | Yellow Zinc |
| Size Name | 3/8" x 5-1/2" Standard Nut |
| Item Shape | Round |
| Unit Count | 10.0 Count |
| Thread Size | 3/8"-16 |
| Finish Types | Yellow Zinc |
| Manufacturer | Quantum Forge |
| Fastener Type | Bolt |
| Item Diameter | 0.38 Inches |
| Material Type | Alloy Steel |
| Item Dimensions | 5.5 x 0.38 x 0.38 inches |
| Number of Pieces | 10 |
| Screw Head Style | Hex |
| Maximum Shear Strength | 150,000 psi min tensile |
Bestseller ranking
Sleep Supplements
Customers who viewed this product also viewed
Hex Bolts
Correction of product information
If you notice any omissions or errors in the product information on this page, please use the correction request form below.
Correction Request Form