M3 x 3mm screws — what they fit & where to buy

68 sourced applications in this database list a M3 screw at 3 mm (or a length range that includes it), most of them in cameras & optics. A M3 x 3mm screw has a 0.5 mm coarse pitch, so a fully engaged 3 mm shank gives about 6 thread turns (1× the diameter).

Buy M3 x 3mm screws

TechSpareWarehouse stocks 13 M3 x 3mm listings (black, Phillips flat/low-profile head), most named for the exact device they fit.

These are listings in TechSpareWarehouse's own Amazon store.

On eBay: M3 x 3mm SSD Mounting Screws for HP Desktop 2.5 SATA Drive Replacement 10-Pack

Search tip: stores list these as “M3 x 3mm screw”. Check the thread and length against your old screw before ordering.

Disclosure: TechSpareWarehouse is our own parts store — we earn from these sales. As an Amazon Associate we also earn from qualifying purchases. Fitment data on this site is not changed by what we stock.

M3 x 3mm specs

Thread
M3 × 0.5
Length
3 mm
Thread turns
≈ 6
Length ÷ diameter
1×
Tap drill
2.5 mm
Clearance (close)
3.2 mm
Phillips
PH1
Torx / hex
T10 / 2.5 mm

Length is measured from under the head for pan, wafer and button heads, and overall for flat (countersunk) heads. Neighbouring sizes we track: M3 x 4 mm (55).Going 0.5 mm too long can bottom out in a blind boss or touch a board underneath.

Where M3 x 3mm screws are used

  • Cameras & Optics15
  • Electronics, Racks & Enclosures12
  • Industrial & Machinery7
  • 3D Printing, CNC & Robotics7
  • Displays, TVs & Mounts7
  • Laptops & PCs6
  • Printers, POS & Office6
  • Other Equipment3

More M3 x 3mm listings named for specific devices

Devices that use M3 x 3mm screws (68)

2.5in SATA SSD / HDD

the SFF-8201 standard: four M3 side holes, plus two optional bottom holes on 7mm drives

3-4mm side (short, so it can't touch the PCB) · confirmed · source

2.5in drive trays & caddies

drive bays, laptop caddies and SSD brackets

3-5mm · confirmed · source

NAS drive trays (Synology / QNAP)

M3 for 2.5in SSD side mounting; 3.5in bays are tool-less or 6-32

3-4mm · confirmed · source

Motherboard to case standoffs

ATX boards thread into brass standoffs with M3 machine screws

3-5mm, thin flat/pan head · confirmed · source

Slim optical drives (9.5 / 12.7mm)

bezel and mounting bracket screws, unlike desktop 5.25in bays

3-4mm · reported · source

Prusa MK3S extruder

extruder body, idler and Bondtech gear assembly are M3 throughout

10-40mm (idler M3x40, body M3x10-18) · confirmed · source

Hotends & heat breaks (E3D and clones)

heater block clamp, fan shroud, and headless grub screws

3-4mm grub, 6-10mm shroud · confirmed · source

Fishing reel handle retainer

holds the handle nut retainer plate on baitcasters

3-10mm · confirmed · source

GT2 pulley grub screws

locks the timing pulley onto the motor shaft

3-4mm · reported · source

Dell PowerEdge hard drive caddy (part 2864D)

Caddy securing screw, genuine Dell part M3x3

3mm · reported · source

JUKI sewing machine needle clamp screw

GoldStar Tool sells 'Needle Clamp Screw M3x3' for JUKI sewing machines, part SM-8030312-TP

3mm · confirmed · source

Dell Inspiron 15 5575 laptop

Four screws securing hard-drive bracket to hard drive

3mm · high · source

JUKI industrial sewing machine needle clamp screw (SM-8030312-TP)

Product page explicitly names part 'Needle Clamp Screw M3x3 - JUKI #SM-8030312-TP'

3mm · high · source

GT2 timing pulley grub screws

M3 x 4 hex socket set screws clamping pulley to motor shaft

3-6mm · confirmed · source

Slice Engineering Mosquito hotend

Hot block to heat sink, M3 x 0.5 screws

M3 x 0.5 (2 pcs) · confirmed · source

E3D V6 hotend fixing kit

Kit contains M3x3 and M3x10 socket dome screws

3mm and 10mm · likely · source

Lenovo ThinkPad W700 screw kit

Manual lists M3 x 3mm black wafer head (5 pcs)

3mm · confirmed · source

Panasonic WV-NF5C outdoor camera housing

Cover fixing screws, manual states M3 x 3

3mm · confirmed · source

2.5in SATA / SAS hard drives and SSDs (SFF-8201)

The 2.5in drive form-factor standard tabulates M3 threads for the side and bottom mounting holes

max 2.0mm penetration on 7mm drives, 3.0mm on thicker · confirmed · source

Bondtech 17-tooth steel gear

set screw

3mm · confirmed · source

E3D v6 hotend fixing kit

M3 x 3mm and M3 x 10mm socket dome screws for heater block / nozzle assembly

3-10mm · confirmed · source

Samsara CM33/CM34 dashcam mount

Installation guide explicitly specifies the mount locking screw on both sides as Hex M3

M3 · confirmed · source

1.25" eyepiece/diagonal/SCT visual back thumb screw

Replacement M3-0.5mm thread pitch set/thumb screws explicitly sold for 1.25" diagonal eyepiece and SCT visual back thumbscrews, and some finder/guide scope shoes

M3 · confirmed · source

Telescope accessory thumb screws

Anodized accessory thumb screws explicitly sold in M3 and M4, with M3 commonly used for smaller eyepiece/accessory threads

M3x12, M4x12 · confirmed · source

Celestron 1.25" 2x Ultima Barlow 'shorty' set screw

Screw-size database lists this Barlow's thumb/set screw explicitly as M3-0.5

M3 · confirmed · source

StarTech Universal Projector Wall Mount (PROJWALLMNT)

Included hardware kit lists M3 x 24mm screws for attaching the projector plate to smaller projectors

M3x24 · confirmed · source

Premier Mounts PBL-UMS/PBL-UMW Universal Projector Mount

Included fastener set explicitly lists M3 x 12mm screws for small-format projector adapter plates

M3x12 · confirmed · source

QualGear QG-KIT-VA-3IN-B Projector Mounting Kit

Universal projector plate hardware kit explicitly specifies M3 x 8mm screws

M3x8 · confirmed · source

Melco EMC 1 Embroidery Peripheral (textile printing/embroidery machinery)

Illustrated parts manual lists M3 x 0.5 pitch machine screws used on control/board mounting hardware

M3x0.5 pitch · confirmed · source

Happy HCR Series Computerized Embroidery Machine

Maintenance manual specifies M3 x 6mm screws for internal sensor/board fixation during adjustment procedures

M3x6 · confirmed · source

cab Applicator A3200 print-and-apply labeling system (packaging line hardware)

Service manual specifies M3 fasteners in multiple lengths (M3x4, M3x5, M3x7.5, M3x10, M3x20, M3x25) for internal assembly, sensor brackets and covers

M3x4, M3x5, M3x7.5, M3x10, M3x20, M3x25 · confirmed · source

B-Tek T401S Weight Indicator (industrial weighing scale)

Service manual references M3 machine screws for internal PCB/terminal mounting within the indicator enclosure

M3 (length not fully specified in excerpt) · likely · source

Bluelab PeriPod M3 Automatic Nutrient/pH Dosing Pump (aquarium/hydroponic dosing equipment)

Care and use guide for the PeriPod M3 multi-channel peristaltic doser used on aquarium/reservoir setups; wall-mount bracket is secured using M3 screws per the mounting instructions

M3 (bracket screws) · likely · source

Hillrom Centrella Smart+ Bed control panel/electronics housing

Service manual for the Centrella Smart+ hospital bed documents M3 machine screws used to secure the control panel PCB and pendant housing covers during disassembly/service procedures

M3 (length per specific housing screw, not itemized in excerpt) · likely · source

COSEL power supply terminal block (used in industrial/pump/water-treatment control panels)

COSEL's official terminal block torque FAQ explicitly lists M3 screw diameter with recommended torque 0.36-0.6 N·m for terminal block connections used across their industrial power supplies

M3x6-M3x8 · confirmed · source

J-GUANG 301R / 2EDGK-5.0 & 5.08 PCB screw terminal block

Guide explicitly specifies 'M3 Screw — 0.5 Nm... IEC 60999-1 Standard' used in 5.0mm/5.08mm pitch terminal blocks common in control panels (bakery mixer, car wash, EV kiosk control boards)

M3x6 · confirmed · source

Samsung WA50M7450AW top-load washer service manual - control board/wire harness connector screws

Samsung washer service manual explicitly lists M3 screws for control board and sensor bracket fasteners in its exploded parts diagram torque table

M3x8 · likely · source

Kern PFB precision balance internal hardware

Same service manual explicitly lists 'M3x12,8.8' and 'M3x6' and 'M3x12' fasteners in the balance's internal assembly diagrams

M3x6, M3x12 · confirmed · source

Dell UltraSharp U2725QE monitor

iron cover / USB board to QAP back cover

3mm · confirmed · Source: Dell U2725QE Teardown Instruction

Dell UltraSharp U2725QE monitor

main chassis to display panel (4)

3mm · confirmed · Source: Dell U2725QE Teardown Instruction

HP E24d G4 / E27d G4 monitor

internal chassis frame machine screws (14)

3mm · confirmed · Source: HP E24d/E27d G4 Maintenance and Service Guide

Wurth Elektronik WA-SMSI SMT steel spacer

SMT PCB standoff for mounting boards to housings or other boards

0.5-16mm standoff height · confirmed · Source: we-online.com WA-SMSI product page

Dell Inspiron 15 3520

Hard-drive bracket retention

3 mm · confirmed · source

Bien-Air Dental Handpieces

Headless set screw for handpiece spare parts

3 mm · confirmed · source

Novanta NEMA 23 stepper motor (3 A variant)

front-face tapped mounting holes, 3.18mm deep

tapped 3.18mm deep · confirmed · source

Acer Aspire 5942G

Screw List Table: SCREW M3.0D 3.0L K 4.9D NI

3mm · confirmed · source

Acer Aspire 5332 / 5732Z

Screw List: SCREW M M 3.0D 3.0L K 4.9D NI

3mm · confirmed · source

Bopla DIBLZ distance bolts

Distance bolts for plastic enclosure bosses have M3 internal threads.

M3 internal thread · confirmed · source

Wimberley AP-606 Arca-Swiss lens foot plate

Safety stop screws: "M3 x 3mm Socket Head Cap Screw (Qty 2)"

3 mm · confirmed · source

Celestron C5 Schmidt-Cassegrain OTA secondary mirror collimation screws

Celestron's official knowledge base lists collimation screw thread as M3 x 0.5, 10mm, for the C5 optical tube.

M3x10 mm · confirmed — Celestron Knowledge Base · source

Celestron C6 Schmidt-Cassegrain OTA secondary mirror collimation screws

Official Celestron reference lists M3 x 0.5, 10mm collimation screws for the C6 tube.

M3x10 mm · confirmed — Celestron Knowledge Base · source

Celestron C8 Schmidt-Cassegrain OTA secondary mirror collimation screws

Official Celestron reference lists M3 x 0.5, 8mm collimation screws for the C8 tube.

M3x8 mm · confirmed — Celestron Knowledge Base · source

Celestron C9.25 Schmidt-Cassegrain OTA secondary mirror collimation screws

Official Celestron reference lists M3 x 0.5, 10mm collimation screws for the C9.25 tube.

M3x10 mm · confirmed — Celestron Knowledge Base · source

Celestron C11 Schmidt-Cassegrain OTA secondary mirror collimation screws

Official Celestron reference lists M3 x 0.5, 12mm collimation screws for the C11 tube.

M3x12 mm · confirmed — Celestron Knowledge Base · source

Celestron C14 Schmidt-Cassegrain OTA secondary mirror collimation screws

Official Celestron reference lists M3 x 0.5, 18mm collimation screws for the C14 tube.

M3x18 mm · confirmed — Celestron Knowledge Base · source

Celestron EdgeHD 8" OTA secondary mirror collimation screws

Official Celestron reference lists M3 x 0.5, 12mm collimation screws for the 8" EdgeHD tube.

M3x12 mm · confirmed — Celestron Knowledge Base · source

Celestron EdgeHD 9.25" OTA secondary mirror collimation screws

Official Celestron reference lists M3 x 0.5, 10mm collimation screws for the 9.25" EdgeHD tube.

M3x10 mm · confirmed — Celestron Knowledge Base · source

Celestron EdgeHD 11" OTA secondary mirror collimation screws

Official Celestron reference lists M3 x 0.5, 12mm collimation screws for the 11" EdgeHD tube.

M3x12 mm · confirmed — Celestron Knowledge Base · source

Celestron EdgeHD 14" OTA secondary mirror collimation screws

Official Celestron reference lists M3 x 0.5, 18mm collimation screws for the 14" EdgeHD tube.

M3x18 mm · confirmed — Celestron Knowledge Base · source

NCR SelfServ/POS kiosk Verifone P400 PIN Pad Adapter

NCR service help states: 'Remove two (2) M3 screws to detach the Verifone P400 PIN Pad from the PIN Pad Adapter'

M3 (length not specified) · confirmed — NCR Online Help (onlinehelp.ncr.com) · source

Elo EMV cradle kit, P400 attachment screws

Same Elo assembly manual lists 'P400 Screws Qty.2 Screw, M3x6, Pan Head, Cross Recess, Black'

M3x6 mm · confirmed — Elo Touch Solutions UM600683 · source

Diebold Nixdorf ATM ESC (Encrypting PIN Pad/keyboard) cross screw

Parts listing: 'Diebold Nixdorf ESC Cross Screw M3*4*6 ATM Parts 49221808000F' — screw described explicitly as M3

M3x4x6 mm (head dia x length variant) · confirmed — Diebold Nixdorf OEM parts listing · source

Elo self-service kiosk stand, strap screws

Same manual, Bag C: 'SCREW, M3X8, PAN-HEAD, CROSS-RECESS' Qty.3

M3x8 mm · confirmed — Elo Touch Solutions QIG600074 · source

Elo EMV kit for Verifone MX915/M400, Ingenico ISC250 self-service stand mount

Assembly instructions Bag C: 'SCREW, M3X8, PAN-HEAD' Qty.2

M3x8 mm · confirmed — Elo Touch Solutions QIG600186 · source

Verifone M400 payment terminal rear locking bracket access cover

OEM engineering drawing callout: 'M3 X 8MM BUTTON HEAD SCREW SECURES ACCESS COVER TO VERIFONE M400 REAR LOCKING BRACKET'

M3x8 mm · confirmed — Verifone-compatible mounting bracket engineering drawing (Collage/CDN hosted OEM spec) · source

PEM self-clinching panel fastener used in ATM/kiosk cabinet sheet-metal assembly

PEM PF11-M3 series 'Self Clinching Panel Fastener' explicitly specified as M3 thread, marketed for cabinet/access-panel fastening including ATM manufacturing contexts

M3 (knurled head captive screw) · confirmed — PEM/Zygology official product spec (PF11-M3-1) · source

PEM self-clinching flush-head stud, sheet-metal enclosures (ATM/kiosk/POS chassis use case)

PEM FH-M3-6ZI datasheet: 'Thread Code: M3, Thread Size: M3 x 0.5, Thread Specification: 6g, ASME B1.13M'

M3 x 0.5, 6 mm stud · confirmed — PEM official product finder spec sheet · source

PEM self-clinching nut, stainless, sheet-metal chassis (ATM cabinet manufacturing use case)

PEM CLS-M3-1 datasheet: 'Thread Code: M3, Thread Size: M3 x 0.5, Thread Specification: 6H, ASME B1.13M'

M3 x 0.5 (nut) · confirmed — PEM official product finder spec sheet · source