Black 304 Stainless Steel Eye Bolts and Eye Nuts — M3 to M20 Lifting Hardware

Match the thread diameter to your existing bolt hole or mating fastener. For example, M8 (≈5/16" diameter) is commonly used for light rigging and hanging fixtures. Always verify the thread pitch matches your application — our listings show both diameter and pitch (e.g., M8 × 1.25mm). When in doubt, size up for a safety margin. For shank length, measure the depth of your threaded hole and add enough engagement length — typically at least 1× the bolt diameter for steel, 1.5× for softer materials.

Divide millimeters by 25.4 to get inches. Quick reference: 9mm ≈ 3/8", 12mm ≈ 1/2", 16mm ≈ 5/8", 20mm ≈ 25/32", 25mm ≈ 1", 30mm ≈ 1-3/16", 40mm ≈ 1-9/16", 50mm ≈ 2". Thread diameters: M6 ≈ 1/4", M8 ≈ 5/16", M10 ≈ 3/8", M12 ≈ 1/2", M16 ≈ 5/8", M20 ≈ 3/4".

Working load limits vary by size and installation method. Generally, M3–M5 are suited for light-duty hanging and craft applications, while M8–M20 are typically used for rigging, lifting, and structural anchoring. Always apply a safety factor of at least 4:1 and never exceed the rated working load. Contact us to confirm load ratings for your specific size before use in critical lifting applications.

Yes. The 304 stainless steel base material provides good corrosion resistance in most outdoor environments including rain, humidity, and general coastal exposure. The black oxide finish adds an additional layer of surface protection. For highly corrosive marine or saltwater-immersion environments, 316 stainless steel is generally recommended — please contact us if you need guidance on the right grade for your application.

Yes. These use standard ISO metric coarse threads (e.g., M6 × 1.0mm, M8 × 1.25mm, M10 × 1.5mm). They are compatible with any standard metric nuts, bolts, threaded rods, or threaded inserts of the matching size and pitch. Thread pitch is listed for each variant so you can confirm compatibility before ordering.

Eye bolts have an external threaded shank that screws into a tapped hole or is secured with a nut on the other side of a panel. Eye nuts have an internal thread and are screwed onto a threaded rod or stud bolt. Both feature a closed ring (eye) at the top for attaching hooks, shackles, cables, or ropes. Choose based on your mounting configuration — eye bolts for tapped holes, eye nuts for threaded rods.

These eye bolts and eye nuts are generally suitable for vertical overhead lifting when properly installed and within rated load limits. For angular or side-loading applications, use shoulder-pattern eye bolts and derate the working load accordingly — a 45° angle typically reduces the rated load by approximately 30%. Always follow applicable safety standards (e.g., ASME B30.26) and consult a qualified engineer for critical lifting operations.

For eye bolts: thread fully into a tapped hole with at least 1× the bolt diameter of thread engagement (1.5× recommended for softer base materials). Tighten firmly and orient the eye in the direction of the load. For eye nuts: thread fully onto a stud or rod and tighten against a bearing surface. Avoid cross-threading — hand-start before applying a wrench. Do not use impact tools on stainless steel fasteners as this can cause galling.