GCX barcode scanner adapter base plate screw size
M4 · 20 mm long
The screws used on GCX barcode scanner adapter base plate are M4, 20 mm long.
Where it is used: kit lists M4 x 20 flat head machine screws for base plate mounting.
Head and drive, as the source states them: flat / countersunk head.
This entry is marked confirmed and comes from gcx.com.
An M4 screw is 4 mm in diameter with a 0.7 mm pitch, tapped with a 3.3 mm drill; imperial look-alike: #8-32 (4.17 mm) — the standard US PC/rack screw, close but not the same.
GCX barcode scanner adapter base plate 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 |
|---|---|---|---|---|---|---|
| M4 | 20 mm | 0.7 mm | Flat / countersunk | not stated | Kit lists M4 x 20 flat head machine screws for base plate mounting | Confirmed |
Fitment records and sources
Kit lists M4 x 20 flat head machine screws for base plate mounting
pitch 0.7 mm · tap 3.3 mm · clearance 4.5 mm · PH2 / Torx T20
How to check the screw before you buy
- Industrial parts lists usually give the full callout (thread, length, head, grade); match all four, not just the thread.
- Diameter: across the threads an M4 screw measures about 4 mm with calipers (usually a hair under). If yours measures noticeably more or less, it is a different thread.
- Pitch: 0.7 mm from one thread crest to the next (14.29 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 record states 20 mm. Going longer risks bottoming out or touching parts behind the hole; going shorter loses thread engagement.
- Driver: the source does not name the drive. Standard M4 heads take PH2 for Phillips and T20 for Torx, and a 3 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 M4 is about 2.0-3.0 N·m into metal threads and 0.8-1.4 N·m into plastic bosses; snug it up and stop.
Common mix-ups with M4
- Bopla SHR-Z boss screws and Hammond 1591XXF screws look metric but are self-tapping/imperial — don't substitute a machine screw into those bosses.
- Smart doorbell and lock kits bundle metric machine screws with imperial wood screws in the same bag; the metric ones are rarely labelled.
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 Industrial & Machinery
The same screw also fits
Devices whose records share a thread with GCX barcode scanner adapter base plate, closest length match first.
- Power tool battery pack shell also M4 × 20 mm
- Pinball cabinet hardware (EU restorations) also M4 × 20 mm
- ABB random-wound motor terminal boxes (ACS580 drive systems) also M4 × 20 mm
- LG 65LW6500 also M4 × 20 mm
- Rexel S16 paper shredder also M4 × 20 mm
- Monitor arms (Ergotron LX and generic) also M4 × 20 mm
- LG 42LM6400 also M4 × 20 mm
- Belmont Eurus S6 Dental Unit also M4 × 20 mm
Questions about GCX barcode scanner adapter base plate screws
- What size screw does GCX barcode scanner adapter base plate use?
- M4 × 20 mm for kit lists M4 x 20 flat head machine screws for base plate mounting.
- How long are the screws in GCX barcode scanner adapter base plate?
- The record gives 20 mm. Measure the original from under the head (overall for a countersunk head) to confirm before ordering.
- What is the thread pitch of an M4 screw?
- 0.7 mm (coarse), which is the standard pitch for M4 machine screws; a 0.5 mm fine pitch exists but is uncommon. The tap drill is 3.3 mm and the normal clearance hole is 4.5 mm.
- What screwdriver do I need for GCX barcode scanner adapter base plate?
- The sources do not name the drive. For M4, Phillips heads normally take PH2 and Torx heads T20; socket heads take a 3 mm hex key.
- Can I use an imperial screw instead of M4?
- No. Imperial look-alike: #8-32 (4.17 mm) — the standard US PC/rack screw, close but not the same. Use a true M4 screw so it does not cross-thread or strip the hole.