1/4" equivalent is M6 and the I.D is 0.35mm bigger 1/2" equivalent is M12 and the I.D is 0.7mm smaller 5/16" equivalent is M8 and the I.D is 0.06mm smaller 7/16" equivalent is M12 and the I.D is 0.89mm bigger.
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4-stroke Gasoline High-pressure Washer, Single Cylinder, Air-cooled 7.5HP Gasoline Engine Jet Cleaner
Aliexpress UK
A larger diameter washer ideal for spreading the clamping load, reducing a hole diameter and packing out. Sometimes known as a �mudguard� washer. Plated in Trivalent Chromium (Cr3) Zinc Goods dispatched same day if ordered by 2pm (weekdays only) A VAT Invoice will be sent with the goods Delivery/Postage is to UK mainland only.
eBay
750ML Snow Foam Lance For AR Bosche AQT Makita Black Deck Pressure Washers Soap Foam Generator With Adjustable Sprayer Nozzle
Aliexpress UK
Size: M6 x 19mm. Steel penny washers for nuts, bolts & screws. Steel Penny Repair Washers.
eBay
Lawnmower Parts Brake Handle For 362 365 371 372 372XP Chainsaw Clutch Washer Front Guard Brake Handle
Aliexpress UK
REPAIR WASHERS BRIGHT ZINC PLATED. 5, 10, 20, 30, 50, 100, 200, 500. MILD STEEL. to select size & quantity.
eBay
Gearcase Drain Plug Seal Washer 8M0007119 High Temperature Proof Replacement For Mercruiser Drives
Aliexpress UK
M3 M4 M5 M6 M8 Flat Washers. M4 - 9mm Flat Washers. M4 - 14mm Flat Washers. M8 - 16mm Flat Washers. M4 - 20mm Flat Washers. M8 - 18mm Flat Washers. M8 - 22mm Flat Washers. M8 - 25mm Flat Washers.
eBay
Retractable Design Suitable High Pressure Washer Automatic Hose Ree for Patio Garden Cleaning
Aliexpress UK
Repair Washers/Penny Washers (BZP). M8 x 25 (5/16 x 1). M8 x 38 (5/16 x 1.1/2). M10 x 38 (3/8 x 1.1/2). M10 x 50 (3/8 x 2). M6 x 19 (1/4 x 3/4). M6 x 25 (1/4 x 1). M6 x 38 (1/4 x 1.1/2).
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Motorcycle Carburetor Repair Kit For Honda XR 400 XR400R 1998 - 2004 Carb Diaphragm sealing washer Parts
Aliexpress UK
Ensure secure fastening and long-lasting durability with theseTimco M6 x 20mm large zinc penny/mudguard washers. Perfect for a wide range of DIY, construction, and repair projects, these high-quality steel washers provide exceptional strength and corrosion resistance.
eBay
8pcs 1/4" Inline Fuel Filters, Universal 6mm-7mm Fuel Line Filter, Compatible with Lawn Mower, Snow Blower, Pressure Washer
Aliexpress UK
M6 X 20 STAINLESS PENNY REPAIR WASHERS 25 PACK.
eBay
10PCS M12 M13 M14 M15 M16 M17 M18 M19 M20 Brass Copper Sealing Boat Crush Washer Flat Gasket Ring Sump Plug Oil Seal Fitting
Aliexpress UK