M3 M4 M5 M6 Knurled Thumb Screws Aluminium Hand Grip Knob Bolts 6mm to 20mm Long

Most PC cases and ATX/mATX motherboard trays use M3 screws for drive bays and expansion slots, and M3 or M4 for panel fasteners. Check your case manual or measure the existing threaded holes with a thread gauge or a known M3/M4 bolt before ordering. If you're building a custom enclosure, M4 is a common choice for panels 2–3mm thick, while M3 suits thinner sheet metal or PCB standoffs.

Aluminium thumb screws are designed for light clamping loads — panel retention, access covers, and enclosure lids — not structural joints under vibration or heavy load. For typical PC side panels, 3D printer enclosures, and electronics project boxes, the clamping force from finger-tightening is sufficient. If your application involves significant vibration, consider adding a thread-locking insert or nylon washer.

Anodizing is an electrochemical process that converts the surface of the aluminium into a hard oxide layer, so the color is part of the metal rather than a coating sitting on top. This makes it significantly more scratch-resistant than paint. Normal finger-tightening and removal will not damage the finish. Abrasive contact with sharp metal edges over many cycles may eventually show wear on the knurl peaks.

Yes, provided you use the correct T-nut or drop-in nut for your extrusion profile (typically 2020, 3030, or 4040 series). Select the thread size that matches your T-nut — most 2020 extrusion hardware uses M3 or M4 T-nuts. The thumb screw threads into the T-nut just like any standard metric bolt, giving you tool-free panel or bracket attachment.

The 1-piece option is useful when you need to verify thread fit, head clearance, or color match before committing to a full build quantity. The 10-pack is the practical choice for most builds — a standard PC case typically uses 4–8 thumb screws for side panels alone, and having spares prevents delays if one is lost or cross-threaded. The per-unit cost is lower in the 10-pack.

Length refers to the threaded shank, not including the head. For thin sheet metal panels (1–2mm), a 6mm or 8mm length is typically sufficient. For thicker panels, brackets, or when threading through a spacer, choose 10mm–16mm. If you're threading into a T-nut or threaded insert with limited depth, measure the usable thread depth and select a length that engages at least 1.5× the thread diameter (e.g., at least 6mm of engagement for M4). The M6 x 20mm variant suits deeper assemblies or stacked panels.