20 mm x M3 Countersunk Post Head Anchor, 316 Stainless Steel - CPHA4M4X3

The Countersunk Post Head Anchor, 316 Stainless Steel (External) is an expanding anchor with a countersunk head and a threaded post that drives into masonry or concrete.

A4 (316) stainless steel contains molybdenum (about 2 to 3 per cent), which improves its resistance to chlorides. It is the grade normally chosen for coastal, pool, marine and food-processing settings, and it costs more than A2 (304). Metric sizes are written M followed by the nominal thread diameter in millimetres, so M10 is a 10 mm thread.

This listing has 5 variants covering sizes M3 to M10 and lengths 20 mm to 30 mm. Every size comes in packs of 100.

Austenitic stainless steel is generally non-magnetic, although cold-worked parts can show weak magnetism. In wet conditions, keep stainless steel apart from aluminium and galvanised steel with a washer or sleeve, to reduce the risk of galvanic corrosion.

Where this product is used

• Brackets and fittings on masonry
• Food and beverage processing equipment
• Small sizes for enclosures, instruments and light fittings
• Outdoor fittings exposed to salt air
• Coastal and wet-area masonry fixings
• Fixing to concrete, brick and block

Features

• Expanding sleeve grips in masonry
• Metric thread sizes match the nuts, bolts and tapped holes in most Australian-supplied equipment
• A4 (316) stainless steel with molybdenum, for coastal and chloride-exposed settings
• Countersunk head sits flush
• Supplied in packs of 100
• Choice of 5 sizes, M3 to M10

Key specifications

Selecting the right option

Drill the hole to the diameter and depth in the supplier data, clean the dust out, and check the base material suits an expansion anchor. Loads are not stated here, so check the supplier load data for your base material before use.