2,625 Piece Grade 8 UNC Hex Head Cap Screw Assortment Refill
The 2,625-piece Grade 8 UNC assortment with extra-thick SAE flat washers — without the bin. If you already own a 40-hole bin and your applications call for SAE flat washers rather than the standard USS size, this refill gives you the full 1/4"-20 through 1/2"-13 range with the washer spec you need.
What's Included
- Grade 8 hex head cap screws — 1/4"-20, 5/16"-18, 3/8"-16, 7/16"-14, and 1/2"-13, multiple lengths per size
- Grade 8 hex nuts — matching every bolt size in the kit
- Extra-thick SAE flat washers — one set per diameter
- High-alloy lock washers — one set per diameter
- 2,625 pieces total
- Storage is not included — designed for customers who already own a 40-hole bin
Specifications
| Thread standard | UNC — Unified National Coarse |
| Grade | SAE J429 Grade 8 |
| Tensile strength | 150,000 PSI minimum |
| Finish | Yellow zinc |
| Diameters | 1/4"-20, 5/16"-18, 3/8"-16, 7/16"-14, 1/2"-13 |
| Flat washer type | Extra-thick SAE (narrower OD, greater thickness than normal USS or SAE flat washers) |
| Total pieces | 2,625 |
| Storage included | No — for customers who already own a 40-hole bin |
| Compatible storage | 40-hole metal bin (included with corresponding Starter Kit) |
Best For
- SAE washer applications — SAE flat washers have a smaller outer diameter than USS flat washers and are specified in many OEM and equipment service manuals; if your work calls for SAE, this kit matches that spec exactly
- Tighter bolt patterns — the narrower OD of SAE flat washers fits in recessed holes and tight flange areas where a standard USS washer won't clear
- Heavy equipment and structural assemblies — extra thickness adds load-bearing capability in high-clamping-force applications alongside Grade 8 bolts
- Existing bin owners — if you already have a 40-hole metal bin, this refill restocks it completely with the SAE washer spec without paying for new storage
Looking for USS flat washers instead? The Grade 8 UNC Refill with USS Flat Washers covers the same bolt and nut sizes with a larger-OD washer. Both refills are priced for customers who already own a 40-hole bin.
Don't have a bin yet? The Grade 8 UNC Extra-Thick SAE Starter Kit includes both the fasteners and the 40-hole metal bin.
Starter Kit vs. Refill — Which Do I Need?
| Starter Kit | This Refill | |
| Fasteners (2,625 pcs) | ✓ | ✓ |
| Extra-thick SAE flat washers | ✓ Included | ✓ Included |
| 40-hole metal bin | ✓ Included | — Already own one |
| QR-coded labels | ✓ Included | ✓ Included |
If this is your first purchase, the Starter Kit is the right choice. If you're restocking an existing 40-hole bin, this refill gets you back to full without the cost of new storage.
Shipping & Ordering
- Ships within 1–2 business days from our warehouse
- Volume pricing available — save up to 20% when ordering 3 or more
- Reorder regularly? Ask us about a B2B account with a quarterly restock cadence and custom pricing — contact us