Northern Fasteners
M10 Square Plate Washers BZP | 40x40x5mm | Heavy Duty | Pack of 100
M10 Square Plate Washers BZP | 40x40x5mm | Heavy Duty | Pack of 100
Couldn't load pickup availability
M10 square plate washers in Bright Zinc Plated (BZP) mild steel, 5mm thick — the heavier-duty version of our 3mm square plate washer. The 5mm thickness provides greater load spreading and resistance to deformation under high clamping forces. 40x40mm, 12mm clearance hole. Pack of 100.
Specifications
- Thread size: M10
- Dimensions: 40mm x 40mm
- Thickness: 5mm
- Hole diameter: 12mm
- Material: mild steel
- Finish: Bright Zinc Plated (BZP)
- Pack quantity: 100
Suitable for
- Heavy structural timber and masonry connections
- High-clamping-force applications
- Anywhere the 3mm version may deform under load
Frequently asked questions
When should I use 5mm instead of 3mm?
The 5mm version is better where high bolt torque or long-term clamping load could deform a thinner washer — e.g. post bases, structural frames, heavy timber connections. For lighter duty use, the 3mm version is sufficient.
Is there an HDG version for outdoor use?
Yes — see our M10 HDG square plate washers. Browse all square plate washers.
Delivery
Dispatched within 1 working day. Free delivery on orders over £60.
Complete your order
Northern Fasteners stocks everything you need for a complete, matched assembly. Always pair your fasteners with the same finish throughout — BZP with BZP, HDG with HDG, A4 stainless with A4 stainless — for consistent corrosion protection and a professional result. Browse our full range of hex nuts, washers, threaded rods, and bolt and nut sets to find everything you need.
BZP, HDG or A4 Stainless — which finish do you need?
Choosing the right finish is just as important as choosing the right size. BZP is ideal for indoor and sheltered use. HDG provides heavy-duty corrosion protection for outdoor, structural, and timber applications. A4 Grade 316 Stainless is the choice for marine, coastal, and chemical environments where no rust is acceptable. Read our guide to help you decide.
Why buy from Northern Fasteners?
-
Same-day dispatch
Orders placed before 2pm are dispatched the same working day via tracked courier.
-
Free delivery over £60
Free standard UK delivery on all orders over £60. Tracked and reliable.
-
DIN & ISO standards
All fasteners are manufactured to DIN and ISO standards. Grade 4.8 and 8.8 as standard.
-
Trade & domestic
Competitive pricing for both trade buyers and domestic projects. No minimum order.
Free delivery over £60 — same-day dispatch
Orders placed before 2pm are dispatched the same working day. Spend over £60 and get free standard UK delivery via tracked courier. All our fasteners are manufactured to DIN and ISO standards — properly graded, reliably finished, and competitively priced for trade and domestic buyers alike.
Also need mild steel?
We stock a full range of structural mild steel sections alongside our fasteners — angle iron, box section, flat bar, tube, round bar, and more. Whether you're building a gate, a frame, or a fabrication project, we have the steel and the fasteners to go with it, all in one order.