Special Offers
-
Hex Head Self Driller DIN 7504-K A2 Stainless Steel (6.3 X 25)
1000+ in stockRRP From £8.20 -
Cup Square Bolt DIN 603 A2 Stainless Steel (M6 X 40)
1000+ in stockRRP From £5.70 -
Nylon Insert Nut DIN 985 A2 Stainless Steel (M8)
1000+ in stockRRP From £2.88 -
Socket Set Flat Point Screw ISO 4026 A2 Stainless Steel (M6 X 8)
1000+ in stockRRP From £3.00
-
Rect Sect Spring Washer DIN 127-B A4 Stainless Steel (M12)
1000+ in stockM12 spring washer in A4 stainless steel to DIN 127-B. Exerts continuous axial spring load on the nut face once tightened, resisting loosening under vibration and dynamic loading without thread locking compound. A4 (316) marine grade...RRP From £3.60RRP From £3.60 -
Rect Sect Spring Washer DIN 127-B A4 Stainless Steel (M8)
1000+ in stockM8 spring washer in A4 stainless steel to DIN 127-B. Exerts continuous axial spring load on the nut face once tightened, resisting loosening under vibration and dynamic loading without thread locking compound. A4 (316) marine grade...RRP From £2.26RRP From £2.26 -
Rect Sect Spring Washer DIN 127-B A4 Stainless Steel (M6)
1000+ in stockM6 spring washer in A4 stainless steel to DIN 127-B. Exerts continuous axial spring load on the nut face once tightened, resisting loosening under vibration and dynamic loading without thread locking compound. A4 (316) marine grade...RRP From £2.10RRP From £2.10 -
Flat Washer, Form C BS4320-C A4 Stainless Steel (M12)
1000+ in stockM12 flat washer (Form C, large OD) in A4 stainless steel (316 marine grade) to BS4320-C. The large outer diameter spreads load over a wider area than a standard Form A washer - useful for oversized...RRP From £3.60RRP From £3.60 -
Flat Washer, Form C BS4320-C A4 Stainless Steel (M8)
1000+ in stockM8 flat washer (Form C, large OD) in A4 stainless steel (316 marine grade) to BS4320-C. The large outer diameter spreads load over a wider area than a standard Form A washer - useful for oversized...RRP From £2.15RRP From £2.15 -
Flat Washer, Form C BS4320-C A4 Stainless Steel (M6)
1000+ in stockM6 flat washer (Form C, large OD) in A4 stainless steel (316 marine grade) to BS4320-C. The large outer diameter spreads load over a wider area than a standard Form A washer - useful for oversized...RRP From £1.86RRP From £1.86 -
Flat Washer, Form A DIN 125-A A4 Stainless Steel (M16)
1000+ in stockM16 flat washer in A4 stainless steel (316 marine grade) to DIN 125-A. Distributes clamping load under bolt heads and nuts, protecting timber, aluminium, and coated substrates from crushing or marking. A4 (316) resists saltwater and...RRP From £5.81RRP From £5.81 -
Flat Washer, Form A DIN 125-A A4 Stainless Steel (M12)
1000+ in stockM12 flat washer in A4 stainless steel (316 marine grade) to DIN 125-A. Distributes clamping load under bolt heads and nuts, protecting timber, aluminium, and coated substrates from crushing or marking. A4 (316) resists saltwater and...RRP From £4.36RRP From £4.36 -
Flat Washer, Form A DIN 125-A A4 Stainless Steel (M10)
1000+ in stockM10 flat washer in A4 stainless steel (316 marine grade) to DIN 125-A. Distributes clamping load under bolt heads and nuts, protecting timber, aluminium, and coated substrates from crushing or marking. A4 (316) resists saltwater and...RRP From £3.07RRP From £3.07 -
Flat Washer, Form A DIN 125-A A4 Stainless Steel (M8)
1000+ in stockM8 flat washer in A4 stainless steel (316 marine grade) to DIN 125-A. Distributes clamping load under bolt heads and nuts, protecting timber, aluminium, and coated substrates from crushing or marking. A4 (316) resists saltwater and...RRP From £2.32RRP From £2.32 -
Flat Washer, Form A DIN 125-A A4 Stainless Steel (M5)
1000+ in stockM5 flat washer in A4 stainless steel (316 marine grade) to DIN 125-A. Distributes clamping load under bolt heads and nuts, protecting timber, aluminium, and coated substrates from crushing or marking. A4 (316) resists saltwater and...RRP From £2.22RRP From £2.22 -
Flat Washer, Form A DIN 125-A A4 Stainless Steel (M4)
1000+ in stockM4 flat washer in A4 stainless steel (316 marine grade) to DIN 125-A. Distributes clamping load under bolt heads and nuts, protecting timber, aluminium, and coated substrates from crushing or marking. A4 (316) resists saltwater and...RRP From £2.15RRP From £2.15 -
Dome Nut DIN 1587 A4 Stainless Steel (M10)
1000+ in stockM10 dome nut in A4 stainless steel to DIN 1587. The domed cap covers the exposed end of a bolt thread for a safe, finished appearance - used on outdoor furniture, signage, architectural fixings, and play...RRP From £7.20RRP From £7.20 -
Nylon Insert Nut DIN 985 A4-80 A4 Stainless Steel (M12)
1000+ in stockM12 nyloc nut in A4 marine grade stainless steel to DIN 985. The nylon insert grips the bolt thread under vibration and dynamic loading, resisting loosening without thread locking compound - and re-usable after removal. A4...RRP From £15.60RRP From £15.60 -
Nylon Insert Nut DIN 985 A4-80 A4 Stainless Steel (M10)
1000+ in stockM10 nyloc nut in A4 marine grade stainless steel to DIN 985. The nylon insert grips the bolt thread under vibration and dynamic loading, resisting loosening without thread locking compound - and re-usable after removal. A4...RRP From £13.20RRP From £13.20 -
Nylon Insert Nut DIN 985 A4 Stainless Steel (M8)
1000+ in stockM8 nyloc nut in A4 marine grade stainless steel to DIN 985. The nylon insert grips the bolt thread under vibration and dynamic loading, resisting loosening without thread locking compound - and re-usable after removal. A4...RRP From £8.40RRP From £8.40 -
Nylon Insert Nut DIN 985 A4 Stainless Steel (M6)
1000+ in stockM6 nyloc nut in A4 marine grade stainless steel to DIN 985. The nylon insert grips the bolt thread under vibration and dynamic loading, resisting loosening without thread locking compound - and re-usable after removal. A4...RRP From £6.72RRP From £6.72 -
Nylon Insert Nut DIN 985 A4 Stainless Steel (M5)
1000+ in stockM5 nyloc nut in A4 marins grade stainless steel to DIN 985. The nylon insert grips the bolt thread under vibration and dynamic loading, resisting loosening without thread locking compound - and re-usable after removal. A4...RRP From £5.28RRP From £5.28 -
Hexagon Full Nut DIN 934 A4-80 A4 Stainless Steel (M16)
1000+ in stockM16 hex nut in A4 marine grade stainless steel to DIN 934. Full-height hexagon form, compatible with all M16 bolts, machine screws, and threaded rod to metric coarse pitch. Suitable for general indoor and outdoor assemblies,...RRP From £22.80RRP From £22.80 -
Hexagon Full Nut DIN 934 A4-80 A4 Stainless Steel (M12)
1000+ in stockM12 hex nut in A4 marine grade stainless steel to DIN 934. Full-height hexagon form, compatible with all M12 bolts, machine screws, and threaded rod to metric coarse pitch. Suitable for general indoor and outdoor assemblies,...RRP From £14.40RRP From £14.40 -
Hex Socket Countersunk Screw ISO 10642 A4 Stainless Steel (M8 X 25)
1000+ in stockM8 x 25mm countersunk socket screw in A4 marine grade stainless steel to ISO 10642. Hex key driven with a flush countersunk head - suited to machinery panels, access covers, and cabinetwork where a clean surface...RRP From £7.94RRP From £7.94 -
Hex Socket Countersunk Screw ISO 10642 A4-70 A4 Stainless Steel (M6 X 30)
1000+ in stockM6 x 30mm countersunk socket screw in A4 marine grade stainless steel to ISO 10642. Hex key driven with a flush countersunk head - suited to machinery panels, access covers, and cabinetwork where a clean surface...RRP From £5.10RRP From £5.10 -
Hex Socket Countersunk Screw ISO 10642 A4 Stainless Steel (M6 X 20)
1000+ in stockM6 x 20mm countersunk socket screw in A4 marine grade stainless steel to ISO 10642. Hex key driven with a flush countersunk head - suited to machinery panels, access covers, and cabinetwork where a clean surface...RRP From £4.80RRP From £4.80 -
Hex Socket Countersunk Screw ISO 10642 A4-70 A4 Stainless Steel (M5 X 25)
1000+ in stockM5 x 25mm countersunk socket screw in A4 marine grade stainless steel to ISO 10642. Hex key driven with a flush countersunk head - suited to machinery panels, access covers, and cabinetwork where a clean surface...RRP From £4.12RRP From £4.12 -
Hexagon Socket Button Screw ISO 7380-1 A4 Stainless Steel (M6 X 20)
1000+ in stockM6 x 20mm button head socket screw in A4 marine grade stainless steel to ISO 7380-1. The wide, low-profile dome head distributes load across a larger bearing surface than a cap screw, ideal for furniture, signage,...RRP From £4.13RRP From £4.13
A4 (316) is marine grade stainless steel. The molybdenum in the alloy resists the chloride pitting that attacks ordinary stainless in salt air, so A4 is the grade to specify anywhere salt, chlorine or constant damp is part of the environment.
This collection brings together every A4 (316) fastener Simfix stocks, covering hex bolts, carriage bolts, socket caps, machine screws, wood screws, self-tapping screws, nuts and washers, all manufactured to DIN, ISO or BS standards.
When to choose A4 (316)
- Boats, jetties, pontoons and rigging hardware
- Coastal buildings, balconies and anything within reach of salt spray
- Swimming pools and changing rooms, where chlorine is present
- Bathrooms, wet rooms and kitchens that stay humid
When A2 (304) is enough
For indoor work, workshops, and garden structures away from the coast, A2 (304) stainless steel gives full corrosion resistance at a lower cost. A4 is worth the uplift where chlorides are present, not as a blanket upgrade.
Every size is available in DIY and Trade pack quantities.