Dashcam / action-cam suction mount ball joint screw size
M4 · 6 to 8 mm long
The screws used on Dashcam / action-cam suction mount ball joint are M4 in lengths from 6 to 8 mm.
It is listed for mount ball joint locked by an M4 grub screw; the 1/4"-20 is the separate camera thread.
Head and drive, as the source states them: set screw (headless) head.
This entry is marked confirmed and comes from ydboffer.com.
M4 means a 4 mm nominal diameter with a 0.7 mm thread pitch. Imperial look-alike: #8-32 (4.17 mm) — the standard US PC/rack screw, close but not the same.
Dashcam / action-cam suction mount ball joint 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 | 6–8 mm | 0.7 mm | Set screw (headless) | not stated | Mount ball joint locked by an M4 grub screw; the 1/4"-20 is the separate camera thread | Confirmed |
Fitment records and sources
Mount ball joint locked by an M4 grub screw; the 1/4"-20 is the separate camera thread
pitch 0.7 mm · tap 3.3 mm · clearance 4.5 mm · PH2 / Torx T20
How to check the screw before you buy
- Camera and optics hardware often uses short screws into thin threaded plates, so check engagement before tightening fully.
- 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: for set screw (headless) screws, measure from under the head to the tip (countersunk heads are the exception: they 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 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
- Dashcam mounts advertised as '1/4" M4 screw joint' have two different threads: the 1/4"-20 camera thread and a separate M4 grub screw for the ball joint — don't order the wrong one.
- 'Semus' in the Kern manual is a brand/head-style qualifier on the screw, not a separate thread designation — the metric callout is still plainly M4.
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Browse all 278 in Cameras & Optics →The same screw also fits
Devices whose records share a thread with Dashcam / action-cam suction mount ball joint, closest length match first.
- DJI RS upper quick-release plate also M4 × 6–8 mm
- Cognex In-Sight 9000 machine vision system also M4 × 6–8 mm
- Celestron collimation screws, C8/C9.25/C11 SCT optical tubes also M4 × 8 mm
- Telescope finder-scope shoe / base (TS-Optics) also M4 × 6–8 mm
- Vivotek IT9360-H / IT9380-H dome camera also M4 × 8 mm
- OpenFlexure Delta Stage frame also M4 × 6 mm
- Tilta TA-RF-LPL adapter ring support (RED KOMODO cage) also M4 × 8 mm
- Underwater camera housing latch and port also M4 × 6–8 mm
Questions about Dashcam / action-cam suction mount ball joint screws
- What size screw does Dashcam / action-cam suction mount ball joint use?
- M4 × 6–8 mm for mount ball joint locked by an M4 grub screw; the 1/4"-20 is the separate camera thread.
- How long are the screws in Dashcam / action-cam suction mount ball joint?
- 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 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 Dashcam / action-cam suction mount ball joint?
- 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.