Stainless Steel Masonry Expansion Bolts — Reliable Anchoring in Concrete, Brick & Block
Whether you're mounting a structural bracket to a concrete wall, securing a handrail to a brick pillar, or anchoring equipment to a masonry floor, finding an anchor bolt that won't corrode, loosen, or fail under load is non-negotiable. Contractors, maintenance professionals, and serious DIYers all face the same frustration: generic zinc-plated anchors that rust out within a season outdoors or strip under torque. These stainless steel masonry expansion bolts are built to stay put.
Each bolt is a sleeve-style expansion anchor machined from solid stainless steel rod — available in A2 (grade 304) for standard environments and A4 (grade 316) for coastal, marine, or chemically aggressive settings. Thread diameters run from M6 (≈1/4") through M20 (≈3/4"), with lengths from 50mm (≈2") up to 250mm (≈9.8"), covering the full range of light-duty to heavy-duty anchoring tasks. Order in quantities of 1, 5, or 10 pieces to match your project scope.
Typical applications include fixing structural steel brackets and angle irons to reinforced concrete columns, anchoring fence posts and gate hardware to brick or block walls, securing machinery bases and equipment frames to concrete floors, and installing handrails, balustrades, and safety barriers in outdoor or marine environments where A4 stainless steel concrete anchor bolts are required by specification.
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Compatibility: Designed for solid concrete, brick, natural stone, and dense block. Thread standard: ISO metric coarse (M6–M20). Requires a hammer drill or rotary hammer with a matching-diameter masonry bit. Not suitable for hollow or aerated lightweight blocks.
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Confirm your size before ordering: Bolt length shown is the total anchor length. Add your fixture thickness to the required embedment depth to determine the correct length. If unsure, contact us to confirm.
✅ Key Features of These Stainless Steel Masonry Expansion Bolts
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🛡️A2 & A4 Stainless Steel Construction — Choose A2 (304) for general outdoor use or A4 (316) for coastal and marine environments where chloride resistance is critical for stainless steel concrete anchor bolts.
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📐Wide Size Range: M6 to M20 — Covers light-duty M6 anchors for shelving and fixtures through heavy-duty M20 expansion bolts for structural steel connections, all in one product line.
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📏Multiple Lengths: 50mm–250mm — From 50mm (≈2") for thin-section masonry to 250mm (≈9.8") for deep embedment in thick concrete slabs, giving you the right embedment depth for every application.
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⚙️Sleeve Expansion Mechanism — The torque-controlled sleeve expands radially against the drill hole wall as the bolt is tightened, creating a secure mechanical lock in solid concrete and brick without adhesive.
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🔧Standard ISO Metric Thread — M6–M20 coarse metric thread is compatible with standard nuts, washers, and threaded rod couplers, making these masonry wall anchor bolts easy to integrate into existing assemblies.
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📦Flexible Pack Sizes — Available in 1, 5, or 10-piece packs so you can buy exactly what you need — whether it's a single replacement anchor or a full project supply of concrete sleeve anchors.
📐 Technical Specifications — Stainless Steel Masonry Expansion Bolts
| Product Type |
Sleeve-style expansion anchor bolt (torque-controlled) |
| Thread Diameter |
M6, M8, M10, M12, M14, M16, M20 — see variant options |
| Bolt Length |
50mm (≈2"), 60mm (≈2.4"), 70mm (≈2.8"), 80mm (≈3.1"), 90mm (≈3.5"), 100mm (≈3.9"), 110mm (≈4.3"), 120mm (≈4.7"), 150mm (≈5.9"), 200mm (≈7.9"), 250mm (≈9.8") — see variant options |
| Material Grade |
A2 Stainless Steel (AISI 304) or A4 Stainless Steel (AISI 316) — see variant options |
| Thread Standard |
ISO metric coarse thread (DIN 976 / ISO 261) |
| Drive / Installation |
Torque wrench or spanner on hex nut; requires hammer drill with matching masonry bit |
| Base Material |
Solid concrete, brick, natural stone, dense block |
| Finish |
Natural stainless steel (no coating) |
| Pack Quantity |
1 pc, 5 pcs, or 10 pcs — see variant options |
| Tensile / Shear Capacity |
Contact us to confirm — varies by diameter, embedment depth, and base material |
| Country of Origin |
Contact us to confirm |
❓ Frequently Asked Questions
How do I choose the right bolt length for my application?
A general rule: the bolt length should be at least 1.5× the diameter of the bolt plus the thickness of the material being fixed. For example, fixing a 10mm-thick bracket with an M8 bolt typically requires a minimum embedment of 40–50mm (≈1.6–2") into the base material, so a 50mm (≈2") or 60mm (≈2.4") bolt is generally appropriate. Always add the fixture thickness to the required embedment depth when selecting total bolt length.
What load can these expansion bolts handle?
Actual load capacity depends on bolt diameter, embedment depth, base material strength, and spacing. In general, M6 bolts in solid concrete typically carry several hundred Newtons in tension; M12 and above can carry several kilonewtons. Always consult a structural engineer for safety-critical applications and refer to the specific load tables for your base material.
Can these bolts be used outdoors or in wet environments?
Yes. A2 (304) stainless steel is suitable for most outdoor and mildly corrosive environments. For coastal areas, swimming pools, or highly corrosive industrial settings, A4 (316) stainless steel is recommended due to its superior resistance to chloride-induced corrosion. Neither grade requires painting or additional coating.
What base materials are these expansion bolts compatible with?
These sleeve-style expansion bolts are designed for solid concrete, brick, block, and natural stone. They are generally not suitable for hollow or lightweight aerated concrete blocks without specialist fixings. Always verify the base material density before installation.
What is the difference between A2 and A4 stainless steel?
A2 (grade 304) stainless steel offers good general corrosion resistance and is suitable for most indoor and standard outdoor applications. A4 (grade 316) adds molybdenum, giving it significantly better resistance to chlorides and salt spray, making it the preferred choice for marine, coastal, and chemically aggressive environments where standard A2 anchors would typically corrode prematurely.
What drill bit size do I need for these expansion bolts?
The drill hole diameter should match the nominal bolt diameter. For example, an M8 bolt typically requires an 8mm masonry or SDS drill bit. The hole depth should be at least equal to the bolt length plus a small clearance (typically 5–10mm) for debris. Always use a hammer drill or rotary hammer for concrete and masonry — a standard drill will not achieve the required penetration.
Are these bolts removable after installation?
These are torque-controlled expansion anchors. Once fully expanded in concrete, removal is generally not recommended as it can damage the base material. If removability is required, consider a through-bolt or drop-in anchor design instead. In most cases, the bolt can be cut flush if removal of the fixture is needed.
🛒 Select your thread diameter, length, and material above, then add to cart — ships from our US warehouse.
