Knurled Thumb Screws A2 Stainless Steel — Flat Head Thumbscrew Bolts M2 M2.5 M3 M4 M5 M6 M8

Match the thread diameter (M2, M3, M4, etc.) to your tapped hole or nut. For length, the screw should generally engage at least 1–1.5× the thread diameter in depth. For example, an M3 screw typically needs at least 3–4.5mm of thread engagement. Convert mm to inches by dividing by 25.4 — so 10mm ≈ 0.39", 20mm ≈ 0.79", 30mm ≈ 1.18".

A2 stainless steel thumb screws are generally suitable for light-to-medium clamping and panel-fastening tasks. They are not typically rated for high-torque structural applications. For exact tensile values, contact us to confirm based on your specific size and length.

Yes. A2 stainless steel (equivalent to 304 grade) offers good corrosion resistance in most outdoor and humid environments. It is generally suitable for indoor electronics, light outdoor fixtures, and marine-adjacent applications, though prolonged exposure to saltwater or harsh chemicals may cause surface staining over time.

These are metric thread thumb screws following the ISO metric standard (M2 through M8). They are not compatible with UNC/UNF imperial threads. Ensure your tapped holes or nuts are metric before ordering.

No tools are required for typical use. The knurled head is designed for hand-tightening, making them ideal for applications that require frequent adjustment or removal. For higher clamping force, a coin or flat-head driver can generally be used on the flat head profile.

These knurled thumb screws are commonly used in electronics enclosures, 3D printer frames, camera equipment, laboratory instruments, DIY projects, and panel assemblies where tool-free access is needed. They are generally not recommended for high-vibration structural joints without thread-locking compound.

Pack quantities vary by size and are available in 1, 2, 5, 10, 20, 25, and 50 pieces depending on the selected size/length combination. For a single repair or prototype, a 1–5 pc pack is typically sufficient. For production runs or stocking a workshop, the 25 or 50 pc packs offer better per-unit value.