Stainless Steel Expansion Bolts for Masonry — M6 M8 M10 M12 Wall Anchor Screws

Match the bolt diameter to your fixture's hole size — M6 (≈1/4"), M8 (≈5/16"), M10 (≈3/8"), M12 (≈1/2"). For length, add the fixture thickness to the minimum embedment depth, which is typically 25–40mm depending on diameter. Example: mounting a 10mm bracket with an M8 bolt generally requires at least 60mm total length (10mm fixture + 50mm embedment). When in doubt, go one size longer for added holding strength.

Load capacity depends on bolt diameter, embedment depth, and base material strength. Generally, M6 bolts handle lighter loads (typically up to ~1 kN shear in standard concrete), while M12 bolts support significantly heavier loads. Actual values vary with concrete grade and installation quality. Always consult a structural engineer for safety-critical or overhead applications.

304 stainless steel offers good corrosion resistance and is generally suitable for outdoor and humid environments such as patios, garages, and covered exterior walls. For coastal or highly corrosive environments, 316 stainless steel is typically recommended. 201 stainless steel is better suited for dry or mildly humid indoor applications where cost is a factor.

These are metric fasteners following ISO/DIN thread standards. M6, M8, M10, and M12 refer to the nominal thread diameter in millimeters. They are not compatible with UNC or UNF imperial threads. Standard metric nuts and washers will fit these bolts.

These expansion bolts are designed for use in solid concrete, brick, block, and other masonry substrates. The wedge-expansion mechanism requires a solid, dense material to grip against. They are not recommended for hollow walls, drywall, wood, or soft materials where the sleeve cannot expand properly and achieve a secure hold.

304 stainless steel contains higher nickel content (typically 8–10%), giving it better corrosion resistance — ideal for outdoor, damp, or mildly corrosive settings. 201 stainless steel uses manganese instead of nickel, making it a more cost-effective option with slightly lower corrosion resistance. Choose 201 for dry indoor applications or budget-sensitive bulk projects, and 304 for any exposure to moisture or outdoor conditions.

Installation typically requires a hammer drill with a masonry bit matching the bolt's nominal diameter (e.g., a 10mm carbide-tipped bit for M10 bolts). After inserting the bolt, tighten the nut with a wrench or socket set to expand the sleeve against the bore wall. Drill depth should match or slightly exceed the bolt's embedment length.

Most shelf brackets use 2–4 anchor points per bracket. A standard two-bracket shelf installation typically requires 4–8 bolts. For structural applications like handrails or equipment mounts, consult the fixture manufacturer's specifications. Our pack sizes (1, 2, 4, 5, 10, 20, 25, 50 pcs) let you order exactly what you need without waste.