SkyWatcher-style finderscope bracket shoe (2-hole) screw size
M4 · length not stated in the sources
If you are replacing a screw on SkyWatcher-style finderscope bracket shoe (2-hole), the thread is M4. None of the sources we found gives an exact length, so measure the original before you order.
Where it is used: retailer product listing explicitly titled 'SkyWatcher-style Shoe for Finderscope Bracket with 2 Holes - BLACK - M4 Screws', confirming M4 mounting screws for the finder shoe.
This entry is marked confirmed and comes from 365astronomy.com.
For reference, M4 is 4 mm across the threads at 0.7 mm pitch. The imperial size people confuse it with: #8-32 (4.17 mm) — the standard US PC/rack screw, close but not the same.
SkyWatcher-style finderscope bracket shoe (2-hole) 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 | not stated | 0.7 mm | not stated | not stated | Retailer product listing explicitly titled 'SkyWatcher-style Shoe for Finderscope Bracket with 2 Holes - BLACK - M4 Screws', confirming M4 mounting screws for the finder shoeblack finish | Confirmed |
Fitment records and sources
Retailer product listing explicitly titled 'SkyWatcher-style Shoe for Finderscope Bracket with 2 Holes - BLACK - M4 Screws', confirming M4 mounting screws for the finder shoe
pitch 0.7 mm · tap 3.3 mm · clearance 4.5 mm · PH2 / Torx T20
How to check the screw before you buy
- Phone and wearable screws are tiny and often differ by fractions of a millimetre between positions; keep each one next to the hole it came from.
- 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: 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 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
- Not all telescope/finder hardware is metric — Celestron Edge/NexStar SE finder-shoe and dovetail screws are reported as 8/32 (imperial UNC), so metric M4/M5 fitments cannot be assumed across all Celestron products; must check per accessory/vintage.
- '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.
More in Phones, Tablets & Wearables
The same screw also fits
Devices whose records share a thread with SkyWatcher-style finderscope bracket shoe (2-hole), closest length match first.
- SkyWatcher-style finderscope shoe/bracket also M4
- Smart lock interior module also M4
- Ring video doorbell mounting hardware also M4
- WatchGas Tox Point 1000 gas detector transmitter also M4
- Tablet / POS dock mounts also M4
- Speaker driver to baffle also M4
- Dell U2419HC also M4
- Mini PC / thin client VESA adapter kit also M4
Questions about SkyWatcher-style finderscope bracket shoe (2-hole) screws
- What size screw does SkyWatcher-style finderscope bracket shoe (2-hole) use?
- M4 for retailer product listing explicitly titled 'SkyWatcher-style Shoe for Finderscope Bracket with 2 Holes - BLACK - M4 Screws', confirming M4 mounting screws for the finder shoe.
- How long are the screws in SkyWatcher-style finderscope bracket shoe (2-hole)?
- 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 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 SkyWatcher-style finderscope bracket shoe (2-hole)?
- 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.