M6 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 finish is required. A4 (316) gives outstanding saltwater and chloride resistance for marine, coastal, and pool use. Free next-day UK delivery on orders over £50.
  • M6 x 20mm countersunk socket screw marine grade 316 ISO 10642
  • ISO 10642 countersunk socket screw M6 x 20mm A4 marine grade stainless steel, side profile
  • Allen key countersunk detail - M6 x 20mm A4 stainless CSK socket screw ISO 10642
  • Simfix product label - 10642A406020PK10-SIM
  • Simfix product label - 10642A406020PK50-SIM
M6 x 20mm countersunk socket screw marine grade 316 ISO 10642
ISO 10642 countersunk socket screw M6 x 20mm A4 marine grade stainless steel, side profile
Allen key countersunk detail - M6 x 20mm A4 stainless CSK socket screw ISO 10642
Simfix product label - 10642A406020PK10-SIM
Simfix product label - 10642A406020PK50-SIM

Simfix

Hex Socket Countersunk Screw ISO 10642 A4 A4 Stainless Steel (M6 X 20)

SKU 10642A406020PK10-SIM
£4.80
Pack size:
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M6 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 finish is required. A4 (316) gives outstanding saltwater and chloride resistance for marine, coastal, and pool use. Free next-day UK delivery on orders over £50.
£4.80
M6 x 20mm countersunk socket screw marine grade 316 ISO 10642 ISO 10642 countersunk socket screw M6 x 20mm A4 marine grade stainless steel, side profile Allen key countersunk detail - M6 x 20mm A4 stainless CSK socket screw ISO 10642 Simfix product label - 10642A406020PK10-SIM Simfix product label - 10642A406020PK50-SIM
M6 x 20mm countersunk socket screw marine grade 316 ISO 10642 ISO 10642 countersunk socket screw M6 x 20mm A4 marine grade stainless steel, side profile Allen key countersunk detail - M6 x 20mm A4 stainless CSK socket screw ISO 10642 Simfix product label - 10642A406020PK10-SIM Simfix product label - 10642A406020PK50-SIM

This M6 x 20mm countersunk socket screw is manufactured to ISO 10642 in A4 stainless steel (316 marine grade). ISO 10642 specifies a flat countersunk head with a 90-degree included angle and internal hex socket drive. Driven with a hex key, the head sits flush with or below the parent material surface - combining the clean, flush finish of a countersunk head with the high torque capability and access flexibility of socket drive. A practical choice for machinery panels, access covers, and fabrication where a flush surface is required but a Pozi or Phillips driver is not preferred.

Typical applications

  • Marine fabrication requiring a flush fastener in saltwater environments
  • Boat deck panels, swimming pool surrounds, and coastal steelwork
  • Offshore and chemical plant where flush mounting and corrosion resistance are needed
  • Food processing and washdown equipment with hygiene requirements

Available in packs of 10 to 50, with free next-day UK delivery on orders over £50 and 30-day no-quibble returns.

Fastener styleCountersunk screw with hex socket drive
StandardISO 10642
MaterialA4 stainless steel (316)
Property classA4
Thread sizeM6
Thread pitch1.0 mm (coarse)
Length20 mm
Head typeCountersunk socket
Drive typeHex socket (Allen)
Surface finishPlain (no plating)
HS commodity code7318156290
Recommended useMarine

RoHS and REACH compliant.

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