Molex Secured Wall Mount Fiber Enclosure (DSC/QLC UNLDD) screw size
M3 / M4 · 16 to 35 mm long
Molex Secured Wall Mount Fiber Enclosure (DSC/QLC UNLDD) takes M3 and M4 metric screws in lengths from 16 to 35 mm.
There are 3 separate fitment records for it, including 2x M3x35mm screws with M3 hex nuts fastening the splice tray to the enclosure base (M3), M4 countersunk screws securing the second (inner) door of the enclosure (M4) and 4x M4x16mm mounting screws with M4 hex nuts used to mount the enclosure into a rack via M4 (M4).
Head and drive, as the sources state them: flat / countersunk head.
3 of the 3 records are marked confirmed, drawn from 1 source (molexces.com).
An M3 screw is 3 mm in diameter with a 0.5 mm pitch, tapped with a 2.5 mm drill; imperial look-alike: #5-40 (3.18 mm) or #4-40 — neither interchanges with M3.
Molex Secured Wall Mount Fiber Enclosure (DSC/QLC UNLDD) 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 |
|---|---|---|---|---|---|---|
| M3 | 35 mm | 0.5 mm | not stated | not stated | 2x M3x35mm screws with M3 hex nuts fastening the splice tray to the enclosure base | Confirmed |
| M4 | not stated | 0.7 mm | Flat / countersunk | not stated | M4 countersunk screws securing the second (inner) door of the enclosure | Confirmed |
| M4 | 16 mm | 0.7 mm | not stated | not stated | 4x M4x16mm mounting screws with M4 hex nuts used to mount the enclosure into a rack via M4 screw slots | Confirmed |
Fitment records and sources
2x M3x35mm screws with M3 hex nuts fastening the splice tray to the enclosure base
pitch 0.5 mm · tap 2.5 mm · clearance 3.4 mm · PH1 / Torx T10
M4 countersunk screws securing the second (inner) door of the enclosure
pitch 0.7 mm · tap 3.3 mm · clearance 4.5 mm · PH2 / Torx T20
4x M4x16mm mounting screws with M4 hex nuts used to mount the enclosure into a rack via M4 screw slots
pitch 0.7 mm · tap 3.3 mm · clearance 4.5 mm · PH2 / Torx T20
How to check the screw before you buy
- Rack and enclosure hardware mixes metric and imperial (#8-32, #10-32, #6-32), so confirm the thread before forcing a screw.
- Diameter: across the threads an M3 screw measures about 3 mm with calipers (usually a hair under). This device also uses M4, so measure each screw rather than assuming they match.
- Pitch: 0.5 mm from one thread crest to the next (20 crests per centimetre). A thread pitch gauge or the pitch-gauge tool settles it in seconds.
- Length: the source describes a countersunk (flat) head, and those are measured overall, from the top of the head to the tip.
- The records span 16–35 mm, which means different positions take different lengths — match each hole to its own screw.
- Driver: the source does not name the drive. Standard M3 heads take PH1 for Phillips and T10 for Torx, and a 2.5 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 M3 is about 80-130 N·cm into metal threads and 35-60 N·cm into plastic bosses; snug it up and stop.
Common mix-ups with M3 / M4
- LED wall cabinets use different threads at different points - M3 on bezels, M4 on frame links and tops, M6 on frame joints. 'An M4 for the LED wall' is not enough information.
- 2020 extrusion T-nuts come in M3/M4/M5 and are not interchangeable — M3 is accessory-only, M5 is structural.
- Some rackmount KVM switch kits pair M4x10 bracket-to-rack screws with M3.2x4.5 bracket-to-chassis screws (non-standard M3.2, not a true M3), so kits are not fully interchangeable with generic M3/M4 hardware.
- Display mounts mix systems: the screen side is metric M4/M6, but the wall side of many mounts uses imperial wood screws such as #14 x 2.5in.
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.
More in Electronics, Racks & Enclosures
The same screw also fits
Devices whose records share a thread with Molex Secured Wall Mount Fiber Enclosure (DSC/QLC UNLDD), closest length match first.
- cab Applicator A3200 print-and-apply labeling system (packaging line hardware) also M4 × 16 mm
- Metcase Technomet-Control instrument enclosure also M4 × 16 mm
- Refrigerator door handle also M4 × 16 mm
- Rack PDU ears also M4 × 16 mm
- Ubiquiti UniFi AP ceiling mount also M3 × 35 mm
- Wurth Elektronik WA-SPAIE plastic spacer stud also M3 × 35 mm
- Wurth Elektronik WA-SSTIE steel spacer stud also M3 × 35 mm
- Instrument enclosure bezel screws (Metcase Technomet-Control) also M4 × 16 mm
Questions about Molex Secured Wall Mount Fiber Enclosure (DSC/QLC UNLDD) screws
- What size screw does Molex Secured Wall Mount Fiber Enclosure (DSC/QLC UNLDD) use?
- M3 × 35 mm for 2x M3x35mm screws with M3 hex nuts fastening the splice tray to the enclosure base; M4 for M4 countersunk screws securing the second (inner) door of the enclosure; M4 × 16 mm for 4x M4x16mm mounting screws with M4 hex nuts used to mount the enclosure into a rack via M4 screw slots.
- How long are the screws in Molex Secured Wall Mount Fiber Enclosure (DSC/QLC UNLDD)?
- The records range from 16 to 35 mm depending on the position, so match each screw to its own hole.
- What is the thread pitch of an M3 screw?
- 0.5 mm (coarse), which is the standard pitch for M3 machine screws; a 0.35 mm fine pitch exists but is uncommon. The tap drill is 2.5 mm and the normal clearance hole is 3.4 mm.
- What screwdriver do I need for Molex Secured Wall Mount Fiber Enclosure (DSC/QLC UNLDD)?
- The sources do not name the drive. For M3, Phillips heads normally take PH1 and Torx heads T10; socket heads take a 2.5 mm hex key.
- Can I use an imperial screw instead of M3?
- No. Imperial look-alike: #5-40 (3.18 mm) or #4-40 — neither interchanges with M3. Use a true M3 screw so it does not cross-thread or strip the hole.