M3 Screws

M3 is the metric thread used through most water cooling hardware: radiator fan mounting on European rads, block covers, pump tops and bracket hardware.

Radiator and fan mounting is where length matters most. Alphacool covers M3 x 5mm flat head through M3 x 15mm, M3 x 30mm, M3 x 35mm and M3 x 37mm, plus M3 radiator screws with 34mm spacers, so you can match the exact stack of rad, gasket, shroud and fan you are actually building.

ModMyMods supplies the widest range of individual M3 lengths and head styles, and DimasTech covers M3 thumb screws for bench hardware.

Work out the stack before ordering: fan thickness plus shroud plus gasket plus the depth the screw needs to bite. A screw that is 3mm too long goes straight into a radiator fin channel.

Imperial hardware is in 6-32 screws and the rest is in screws.