What size screw does Eurorack module/rail mounting screw use?

M2.5 × 8 mm for synthRacks sells M2.5 machine screws used to fix modules to Vector rails or Schroff rails with M2.5 nuts and threaded rails; 8mm length recommended when case uses washers; M3 × 6 mm for shunTool states the Eurorack standard screw is M3, used with fixed nut strips and with SynthRacks, GieTec, or TipTop Z rails plus M3 nuts and threaded rails; 6mm M3 screws commonly used.

How long are the screws in Eurorack module/rail mounting screw?

The records range from 6 to 8 mm depending on the position, so match each screw to its own hole.

What is the thread pitch of an M2.5 screw?

0.45 mm (coarse), which is the standard pitch for M2.5 machine screws; a 0.35 mm fine pitch exists but is uncommon. The tap drill is 2.05 mm and the normal clearance hole is 2.9 mm.

What screwdriver do I need for Eurorack module/rail mounting screw?

The sources do not name the drive. For M2.5, Phillips heads normally take PH1 and Torx heads T8; socket heads take a 2 mm hex key.

Can I use an imperial screw instead of M2.5?

No. Imperial look-alike: #3-48 / #4-40 (2.51 / 2.84 mm) — #4-40 is the common US stand-in and it will NOT thread in. Use a true M2.5 screw so it does not cross-thread or strip the hole.

Where can I buy replacement screws for Eurorack module/rail mounting screw?

TechSpareWarehouse (our own store) lists M2.5 x 8mm and M3 x 6mm, which match lengths in the records above.

Eurorack module/rail mounting screw screw size

M2.5 / M3 · 6 to 8 mm long

If you are replacing a screw on Eurorack module/rail mounting screw, the thread is M2.5 and M3 in lengths from 6 to 8 mm.

There are 2 separate fitment records for it, including synthRacks sells M2.5 machine screws used to fix modules to Vector rails or Schroff rails (M2.5) and shunTool states the Eurorack standard screw is M3, used with fixed nut strips and with Syn (M3).

2 of the 2 records are marked confirmed, drawn from 2 sources (synthracks.com and shuntool.com).

An M2.5 screw is 2.5 mm in diameter with a 0.45 mm pitch, tapped with a 2.05 mm drill; imperial look-alike: #3-48 / #4-40 (2.51 / 2.84 mm) — #4-40 is the common US stand-in and it will NOT thread in.

Eurorack module/rail mounting screw screw specifications

One row per fitment record. Head, drive are shown only where the source states them; pitch is the ISO coarse pitch for the thread.

Thread	Length	Pitch	Head	Drive	Where it goes	Status
M2.5	8 mm	0.45 mm	not stated	not stated	SynthRacks sells M2.5 machine screws used to fix modules to Vector rails or Schroff rails with M2.5 nuts and threaded rails; 8mm length recommended when case uses washerswasher / flange face	Confirmed
M3	6 mm	0.5 mm	not stated	not stated	ShunTool states the Eurorack standard screw is M3, used with fixed nut strips and with SynthRacks, GieTec, or TipTop Z rails plus M3 nuts and threaded rails; 6mm M3 screws commonly used	Confirmed

Fitment records and sources

M2.58mm (also shorter lengths available)confirmed

SynthRacks sells M2.5 machine screws used to fix modules to Vector rails or Schroff rails with M2.5 nuts and threaded rails; 8mm length recommended when case uses washers

pitch 0.45 mm · tap 2.05 mm · clearance 2.9 mm · PH1 / Torx T8

Source

M36mmconfirmed

ShunTool states the Eurorack standard screw is M3, used with fixed nut strips and with SynthRacks, GieTec, or TipTop Z rails plus M3 nuts and threaded rails; 6mm M3 screws commonly used

pitch 0.5 mm · tap 2.5 mm · clearance 3.4 mm · PH1 / Torx T10

Source

How to check the screw before you buy

Board standoffs and enclosure bosses set the usable length: the screw should clamp the board without bottoming in the standoff.
Diameter: across the threads an M2.5 screw measures about 2.5 mm with calipers (usually a hair under). This device also uses M3, so measure each screw rather than assuming they match.
Pitch: 0.45 mm from one thread crest to the next (22.22 crests per centimetre). A thread pitch gauge or the pitch-gauge tool settles it in seconds.
Length: measure from under the head to the tip for pan, button, wafer and cap heads; countersunk (flat) heads are measured overall.
The records span 6–8 mm, which means different positions take different lengths — match each hole to its own screw.
Driver: the source does not name the drive. Standard M2.5 heads take PH1 for Phillips and T8 for Torx, and a 2 mm hex key for socket heads; a bit that fits loosely will cam out and strip the head.
Tightening: no device-specific torque is published in these records. The site's general figure for M2.5 is about 45-70 N·cm into metal threads and 20-35 N·cm into plastic bosses; snug it up and stop.

Common mix-ups with M2.5 / M3

Eurorack rail thread depends on rail brand: Vector/SynthRacks rails use M2.5, others use M3.
Commonly confused with imperial 4-40 screws in older medical equipment, but modern GE/Mindray devices explicitly list M2.5 metric threads.
Eurorack is a strong known case with two competing metric standards (M2.5 for Vector rails, M3 for Schroff/DIN-style and 3U threaded rails); mixing rail types requires matching screw/nut thread.
Power-tool gearcase and clamshell screws are usually thread-forming (marked "ST") even when the parts list gives an M-size — a normal machine screw of the same size may not hold in the plastic boss.

Pitch gauge · Screw size finder · Torque guide

Buy these screws at TechSpare Warehouse

In stock and shipped from South Carolina. Our black screws are Phillips wafer head (low profile); match the head style and length to the original before you order.

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The same screw also fits

Devices whose records share a thread with Eurorack module/rail mounting screw, closest length match first.

AutomationDirect DPM-BKT1 panel meter bracket also M3 × 6 mm
Guitar pedal enclosure also M3 × 6 mm
Eurorack synth rails (standard panel mounting) also M3 × 6 mm
Keystone metric hex PCB standoff also M3 × 6 mm
Apple AirPort Extreme internals also M3 × 6 mm
EK-Loop vertical GPU holder also M3 × 6 mm
GPU rear bracket anchor also M3 × 6 mm
Eurorack panel/module mounting screws (standard rail systems) also M3 × 6 mm

Questions about Eurorack module/rail mounting screw screws

What size screw does Eurorack module/rail mounting screw use?: M2.5 × 8 mm for synthRacks sells M2.5 machine screws used to fix modules to Vector rails or Schroff rails with M2.5 nuts and threaded rails; 8mm length recommended when case uses washers; M3 × 6 mm for shunTool states the Eurorack standard screw is M3, used with fixed nut strips and with SynthRacks, GieTec, or TipTop Z rails plus M3 nuts and threaded rails; 6mm M3 screws commonly used.
How long are the screws in Eurorack module/rail mounting screw?: The records range from 6 to 8 mm depending on the position, so match each screw to its own hole.
What is the thread pitch of an M2.5 screw?: 0.45 mm (coarse), which is the standard pitch for M2.5 machine screws; a 0.35 mm fine pitch exists but is uncommon. The tap drill is 2.05 mm and the normal clearance hole is 2.9 mm.
What screwdriver do I need for Eurorack module/rail mounting screw?: The sources do not name the drive. For M2.5, Phillips heads normally take PH1 and Torx heads T8; socket heads take a 2 mm hex key.
Can I use an imperial screw instead of M2.5?: No. Imperial look-alike: #3-48 / #4-40 (2.51 / 2.84 mm) — #4-40 is the common US stand-in and it will NOT thread in. Use a true M2.5 screw so it does not cross-thread or strip the hole.
Where can I buy replacement screws for Eurorack module/rail mounting screw?: TechSpareWarehouse (our own store) lists M2.5 x 8mm and M3 x 6mm, which match lengths in the records above.

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