M12 T-Bolt Square Head Screws for T-Slot Aluminum Profile — Stainless Steel A2 304

Measure the total thickness of the materials being clamped, then add the engagement depth of the T-slot channel (typically 6–8mm for standard 40-series profiles). For example, if you're clamping 20mm of material, a 30mm (≈1-3/16") bolt is generally a good starting point. Always verify the slot depth of your specific profile before ordering.

These M12 square head T-bolts are designed for T-slot aluminum extrusion profiles that accept an M12 T-nut. They are generally compatible with 40-series and 45-series aluminum profiles. Compatibility with 30-series or other slot widths depends on the specific slot dimensions — please confirm your profile's T-slot width and depth before ordering.

Yes. These bolts are made from A2-70 stainless steel (AISI 304), which provides good corrosion resistance in most outdoor and humid environments. They are generally suitable for light marine, garden, and workshop applications. For highly corrosive or saltwater environments, A4 (316) stainless steel is typically recommended instead.

A2-70 stainless steel bolts have a minimum tensile strength of 700 MPa (approximately 101,500 psi) and a proof load stress of 450 MPa per ISO 3506. For M12 bolts, this translates to a typical proof load of around 50–55 kN, though actual load capacity depends on the clamping configuration and profile material.

Yes. These are M12 metric coarse thread bolts with a standard pitch of 1.75mm per ISO 261/262. They are compatible with standard M12 metric hex nuts, flange nuts, and T-nuts. They are not compatible with UNC/UNF inch-standard fasteners.

The square head profile is specifically designed to seat and lock inside T-slot channels without rotating when a nut is tightened from the other side. This makes assembly faster and easier — no need to hold the bolt head with a second wrench. Hex head bolts generally cannot self-lock inside a T-slot channel the same way, making them impractical for most extrusion assembly work.

Yes. The threaded shank is standard M12 × 1.75mm metric coarse, so it is compatible with any standard M12 hex nut, flange nut, or T-nut. For T-slot assembly, a T-nut is typically inserted into the channel first, and the square head bolt is dropped in from the end or slid into the slot before tightening.

Available lengths range from 20mm to 100mm. Quick reference: 20mm ≈ 3/4", 25mm ≈ 1", 30mm ≈ 1-3/16", 40mm ≈ 1-9/16", 55mm ≈ 2-3/16", 60mm ≈ 2-3/8", 70mm ≈ 2-3/4", 80mm ≈ 3-1/8", 100mm ≈ 3-15/16". Select the length based on your clamping stack height plus the T-slot engagement depth of your profile.