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 National Instruments 68-position SCSI-II jacksocket (DAQ cable accessory)?

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.

National Instruments 68-position SCSI-II jacksocket (DAQ cable accessory) screw size

M2.5 · length not stated in the sources

If you are replacing a screw on National Instruments 68-position SCSI-II jacksocket (DAQ cable accessory), the thread is M2.5. None of the sources we found gives an exact length, so measure the original before you order.

It is listed for document explicitly lists '68-Position SCSI-II Jacksocket, M2.5 Screw' and 'SCSI Connector Washers, M2.5, Flat' used on NI DAQ cables/accessories.

This entry is marked confirmed and comes from ni.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.

National Instruments 68-position SCSI-II jacksocket (DAQ cable accessory) 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	not stated	0.45 mm	not stated	not stated	Document explicitly lists '68-Position SCSI-II Jacksocket, M2.5 Screw' and 'SCSI Connector Washers, M2.5, Flat' used on NI DAQ cables/accessorieswasher / flange face	Confirmed

Fitment records and sources

M2.5.348in length variant listed (not purely metric length)confirmed

Document explicitly lists '68-Position SCSI-II Jacksocket, M2.5 Screw' and 'SCSI Connector Washers, M2.5, Flat' used on NI DAQ cables/accessories

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

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). If yours measures noticeably more or less, it is a different thread.
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.
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

NI's other DAQ SCSI jackscrews use inch-standard 2-56 UNC threads, not metric — M2.5 applies only to the specific jacksocket kit listed.
Commonly confused with imperial 4-40 screws in older medical equipment, but modern GE/Mindray devices explicitly list M2.5 metric threads.

Pitch gauge · Screw size finder · Torque guide

More in Electronics, Racks & Enclosures

19-inch rack cage nut (light equipment)19-inch rack cage nut (metric square-hole rails)19-inch rack cage nut (mid size)19-inch rack cage nut and panel screw 19-inch rack network and AV gear 19-inch rack-mount audio/AV equipment 19-inch server racks 19in / 10in server rack cage nut and screw kit 19in equipment rack (Kendall Howard cage nuts)19in rack cage nuts (alternate metric)19in rack cage nuts (metric)1U rack-mount PDU (American Denki)

Browse all 357 in Electronics, Racks & Enclosures →

The same screw also fits

Devices whose records share a thread with National Instruments 68-position SCSI-II jacksocket (DAQ cable accessory), closest length match first.

Eurorack module-to-rail mounting screws (Vector/SynthRacks rails) also M2.5
D-series audio rack panel screw kit also M2.5
ASUS Chromebox 4 (CN66) also M2.5
Eurorack synth module panels (Befaco Knurlies) also M2.5
Essentra MTNSP-M2.5-11-3 male-to-male standoff also M2.5
Wurth Elektronik WA-SSTIE steel spacer stud also M2.5
Keystone metric nylon standoff also M2.5
Lenovo IdeaPad also M2.5

Questions about National Instruments 68-position SCSI-II jacksocket (DAQ cable accessory) screws

What size screw does National Instruments 68-position SCSI-II jacksocket (DAQ cable accessory) use?: M2.5 for document explicitly lists '68-Position SCSI-II Jacksocket, M2.5 Screw' and 'SCSI Connector Washers, M2.5, Flat' used on NI DAQ cables/accessories.
How long are the screws in National Instruments 68-position SCSI-II jacksocket (DAQ cable accessory)?: None of the sources states a length. Remove one screw and measure it from under the head to the tip (overall for a countersunk head).
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 National Instruments 68-position SCSI-II jacksocket (DAQ cable accessory)?: 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.

Heads up: shipping delay