304 Stainless Steel Through Bolts Wall Expansion Anchor Bolts M6–M20

Generally, the bolt length should equal the thickness of the material being fastened plus the embedment depth required in the base material. For example, if you are fastening a 10mm bracket into concrete, you typically need an embedment of at least 30–40mm, so an M8×50mm (≈2") or M8×60mm bolt would generally be appropriate. Always check the load requirements for your specific application. If in doubt, size up in length — excess thread can be trimmed or accommodated with additional washers.

Load capacity depends on the bolt diameter, embedment depth, and base material. Larger diameters (M12–M20) in solid concrete typically support significantly higher loads than smaller sizes in hollow block. In most cases, M8 bolts in solid concrete can handle moderate structural loads, while M16–M20 are used for heavy machinery and structural steel connections. For safety-critical applications, consult a licensed engineer and refer to the relevant load tables for your specific installation conditions.

Yes. These bolts are made from 304 stainless steel, which provides good resistance to rust and corrosion in most outdoor and humid environments — including rain exposure, garden installations, and exterior wall mounting. For highly aggressive environments such as coastal (salt spray) or chemical-exposure settings, 316 stainless steel is generally recommended instead. If you are unsure, contact us before ordering.

These bolts follow the ISO metric thread standard (M-series, coarse pitch), which is the most widely used fastener standard internationally. They are compatible with standard metric nuts and washers of the corresponding size (e.g., M8 bolt uses an M8 nut). No proprietary hardware is required.

These expansion anchor bolts are designed for solid base materials such as concrete, solid brick, and natural stone. The expansion mechanism requires a solid substrate to grip against. They are generally not suitable for hollow block, drywall, or lightweight materials without additional anchoring hardware. Always verify the base material before installation — using an expansion anchor in an unsuitable substrate can result in fastener pull-out.

Installation typically follows these steps: (1) Drill a hole matching the bolt's nominal diameter into the base material using a hammer drill and masonry bit. (2) Clean dust from the hole. (3) Insert the expansion anchor into the hole. (4) Position your fixture over the bolt. (5) Thread on the nut and tighten — as the nut is tightened, the anchor sleeve expands against the hole wall, creating a secure mechanical grip. Always follow the torque specifications for the bolt size being used. Contact us if you need size-specific installation data.

For light-duty shelf brackets and picture rails, M6 or M8 bolts are typically sufficient. For heavier shelving, kitchen cabinets, or structural brackets, M10 or M12 is generally recommended. For very heavy loads such as machinery mounts, structural steel connections, or overhead lifting points, M16 or M20 may be appropriate. When in doubt, size up — a larger bolt costs little more but provides a meaningful safety margin.

A through bolt (also called a sleeve anchor or expansion bolt) passes through the fixture and into the base material, with the expansion occurring inside the drilled hole as the nut is tightened. This differs from a drop-in anchor or wedge anchor in installation method, but all rely on mechanical expansion in solid substrates. Through bolts are generally preferred when the fixture needs to be removable, as the nut can be loosened and the bolt withdrawn.