Knurled Thumb Screws M3 x 5-100mm Hand Grip Knob Bolts High Type Aluminium Alloy

Most standard ATX and mATX side panels use M3 screws with an effective grip length of 5–10 mm. If your case uses a captive standoff, measure the distance from the panel surface to the bottom of the threaded hole — that measurement is your minimum shaft length. The 5 mm and 8 mm variants cover the majority of thin-panel applications, while 10–15 mm suits thicker sandwich panels or panels with a spacer layer.

For panel-retention duty — holding side panels, access covers, and enclosure lids — aluminium alloy thumb screws provide adequate clamping force when hand-tightened. They are not rated for high-vibration or structural load-bearing applications. If your build is subject to significant vibration (e.g., mounted in a vehicle), consider adding a nylon-insert lock nut on the reverse side or using a thread-locking compound on the first few threads.

Yes. Standard M3 × 0.5 mm heat-set inserts (the most common type used in FDM 3D printing) accept any M3 × 0.5 mm screw. These thumb screws thread directly into those inserts. For best results, choose a shaft length that leaves at least 3–4 mm of thread engagement inside the insert — so for a 4 mm deep insert, a 5 mm or 8 mm shaft is appropriate depending on panel thickness.

Anodizing creates an aluminium oxide layer that improves surface hardness and provides moderate corrosion resistance compared to bare aluminium. All five colour options (Dark Red, Sky Blue, Golden, Silver, Black) go through the same anodizing process, so corrosion resistance is equivalent across colours. These screws are suitable for indoor use and low-humidity environments. For outdoor or high-humidity applications, contact us to confirm suitability.

Yes, with the appropriate T-nut. Standard 2020 and 2040 aluminium extrusion profiles use M3, M4, or M5 T-nuts depending on the slot width. If your extrusion uses M3 T-nuts (common in 2020 profiles with a 6 mm slot), these thumb screws thread directly into them. Pair with a drop-in or roll-in M3 T-nut for tool-free panel attachment to your extrusion frame.

The 1-piece option is useful when you need to replace a single lost or damaged screw, or when you want to test a specific length before committing to a larger quantity. The 5-piece pack offers a lower per-unit cost and is the practical choice for new builds (most panels use 2–4 screws) or when stocking spares. If you need more than 5 pieces, ordering multiple 5-packs is more economical than ordering individual units.

All five colours — Dark Red, Sky Blue, Golden, Silver, and Black — use the same anodizing process and aluminium alloy base material, so mechanical durability and corrosion resistance are identical across the range. The colour choice is purely aesthetic. Black anodizing tends to show fingerprints less visibly, while Silver (natural anodize) is the closest to bare aluminium in appearance.