Lenovo ThinkPad 390 screw size
M2 / M2.5 / M3 · 4 to 18 mm long
Lenovo ThinkPad 390 takes M2, M2.5 and M3 metric screws in lengths from 4 to 18 mm.
There are 19 separate fitment records for it, including display (qty 1, pan) (M2), heat sink (qty 3, pan) (M2) and palm rest (qty 3, pan) (M2), plus 16 more in the table below.
Head and drive, as the sources state them: pan head.
19 of the 19 records are marked confirmed, drawn from 1 source (thinkpad-manuals.retropc.se).
An M2 screw is 2 mm in diameter with a 0.4 mm pitch, tapped with a 1.6 mm drill; imperial look-alike: #2-56 UNC (2.18 mm) is close but not interchangeable.
Lenovo ThinkPad 390 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 |
|---|---|---|---|---|---|---|
| M2 | 10 mm | 0.4 mm | Pan head | not stated | Display (qty 1, pan) | Confirmed |
| M2 | 18 mm | 0.4 mm | Pan head | not stated | Heat sink (qty 3, pan) | Confirmed |
| M2 | 18 mm | 0.4 mm | Pan head | not stated | Palm rest (qty 3, pan) | Confirmed |
| M2 | 18 mm | 0.4 mm | Pan head | not stated | Unspecified (qty 3, pan) | Confirmed |
| M2 | 4 mm | 0.4 mm | not stated | not stated | LED board (qty 1, flat) | Confirmed |
| M2 | 4 mm | 0.4 mm | not stated | not stated | Fan (qty 1, flat) | Confirmed |
| M2 | 4 mm | 0.4 mm | not stated | not stated | Heat sink (qty 4, flat) | Confirmed |
| M2 | 4 mm | 0.4 mm | not stated | not stated | Keyboard (qty 2, flat) | Confirmed |
| M2 | 4 mm | 0.4 mm | not stated | not stated | Palm rest (qty 3, flat) | Confirmed |
| M2 | 4 mm | 0.4 mm | not stated | not stated | Speaker (qty 5, flat) | Confirmed |
| M2 | 4 mm | 0.4 mm | not stated | not stated | Unspecified (qty 2, flat) | Confirmed |
| M2.5 | 4 mm | 0.45 mm | not stated | not stated | Optical drive (qty 4, flat) | Confirmed |
| M2.5 | 6 mm | 0.45 mm | Pan head | not stated | Display (qty 4, flat,pan) | Confirmed |
| M2.5 | 6 mm | 0.45 mm | not stated | not stated | Heat sink (qty 2, flat) | Confirmed |
| M2.5 | 6 mm | 0.45 mm | not stated | not stated | Palm rest (qty 1, flat) | Confirmed |
| M2.5 | 6 mm | 0.45 mm | Pan head | not stated | System board (qty 3, pan) | Confirmed |
| M2.5 | 6 mm | 0.45 mm | Pan head | not stated | Unspecified (qty 3, pan) | Confirmed |
| M3 | 5 mm | 0.5 mm | Pan head | not stated | Hard drive (qty 2, pan) | Confirmed |
| M3 | 5 mm | 0.5 mm | not stated | not stated | Unspecified (qty 4, flat) | Confirmed |
Fitment records and sources
Display (qty 1, pan)
pitch 0.4 mm · tap 1.6 mm · clearance 2.4 mm · PH0 / Torx T6
Heat sink (qty 3, pan)
pitch 0.4 mm · tap 1.6 mm · clearance 2.4 mm · PH0 / Torx T6
Palm rest (qty 3, pan)
pitch 0.4 mm · tap 1.6 mm · clearance 2.4 mm · PH0 / Torx T6
Unspecified (qty 3, pan)
pitch 0.4 mm · tap 1.6 mm · clearance 2.4 mm · PH0 / Torx T6
LED board (qty 1, flat)
pitch 0.4 mm · tap 1.6 mm · clearance 2.4 mm · PH0 / Torx T6
Fan (qty 1, flat)
pitch 0.4 mm · tap 1.6 mm · clearance 2.4 mm · PH0 / Torx T6
Heat sink (qty 4, flat)
pitch 0.4 mm · tap 1.6 mm · clearance 2.4 mm · PH0 / Torx T6
Keyboard (qty 2, flat)
pitch 0.4 mm · tap 1.6 mm · clearance 2.4 mm · PH0 / Torx T6
Palm rest (qty 3, flat)
pitch 0.4 mm · tap 1.6 mm · clearance 2.4 mm · PH0 / Torx T6
Speaker (qty 5, flat)
pitch 0.4 mm · tap 1.6 mm · clearance 2.4 mm · PH0 / Torx T6
Unspecified (qty 2, flat)
pitch 0.4 mm · tap 1.6 mm · clearance 2.4 mm · PH0 / Torx T6
Optical drive (qty 4, flat)
pitch 0.45 mm · tap 2.05 mm · clearance 2.9 mm · PH1 / Torx T8
Display (qty 4, flat,pan)
pitch 0.45 mm · tap 2.05 mm · clearance 2.9 mm · PH1 / Torx T8
Heat sink (qty 2, flat)
pitch 0.45 mm · tap 2.05 mm · clearance 2.9 mm · PH1 / Torx T8
Palm rest (qty 1, flat)
pitch 0.45 mm · tap 2.05 mm · clearance 2.9 mm · PH1 / Torx T8
System board (qty 3, pan)
pitch 0.45 mm · tap 2.05 mm · clearance 2.9 mm · PH1 / Torx T8
Unspecified (qty 3, pan)
pitch 0.45 mm · tap 2.05 mm · clearance 2.9 mm · PH1 / Torx T8
Hard drive (qty 2, pan)
pitch 0.5 mm · tap 2.5 mm · clearance 3.4 mm · PH1 / Torx T10
Unspecified (qty 4, flat)
pitch 0.5 mm · tap 2.5 mm · clearance 3.4 mm · PH1 / Torx T10
How to check the screw before you buy
- A screw that is even 1 mm too long in a laptop base can push into the keyboard, battery or a board trace, so match the length position by position.
- Diameter: across the threads an M2 screw measures about 2 mm with calipers (usually a hair under). This device also uses M2.5 / M3, so measure each screw rather than assuming they match.
- Pitch: 0.4 mm from one thread crest to the next (25 crests per centimetre). A thread pitch gauge or the pitch-gauge tool settles it in seconds.
- Length: for pan head screws, measure from under the head to the tip (countersunk heads are the exception: they are measured overall).
- The records span 4–18 mm, which means different positions take different lengths — match each hole to its own screw.
- Driver: the source does not name the drive. Standard M2 heads take PH0 for Phillips and T6 for Torx, and a 1.5 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 M2 is about 25-40 N·cm into metal threads and 12-20 N·cm into plastic bosses; snug it up and stop.
Common mix-ups with M2 / M2.5 / M3
- The standard M.2 SSD screw is M2 x 3mm, but some laptops and handhelds use non-standard lengths or head shapes.
- Nylon-coated M2.5 screws (ThinkPad Edge) are thread-locking; plain replacements work loose over time.
- 3.5in desktop and enterprise hard drives are 6-32 UNC imperial, not M3 - only the 2.5in form factor is metric.
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.
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ASUS ROG Strix G17 G713 Replacement Screws Sold Individually – M1.6 x 3mm, M2 x 2.5mm, M2 x 3mm, M2.5 x 6mm Phillips Wafer Head, Black
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More in Laptops & PCs
The same screw also fits
Devices whose records share a thread with Lenovo ThinkPad 390, closest length match first.
- HP ENVY 17-r1xx also M2.5 × 4 mm
- Dell Inspiron 14 5401 also M2 × 4 mm
- Dell Inspiron 14 5415 also M2 × 4 mm
- HP Pavilion 5500 also M2 × 4 mm
- HP G7000 also M2 × 4 mm
- Toshiba Satellite 1700 also M2 × 4 mm
- Dell Vostro 15 5502 also M2 × 4 mm
- HP ENVY x360 Convertible also M2.5 × 4 mm
Questions about Lenovo ThinkPad 390 screws
- What size screw does Lenovo ThinkPad 390 use?
- M2 × 10 mm for display (qty 1, pan); M2 × 18 mm for heat sink (qty 3, pan); M2 × 18 mm for palm rest (qty 3, pan); M2 × 18 mm for unspecified (qty 3, pan); M2 × 4 mm for LED board (qty 1, flat); M2 × 4 mm for fan (qty 1, flat); M2 × 4 mm for heat sink (qty 4, flat); M2 × 4 mm for keyboard (qty 2, flat); M2 × 4 mm for palm rest (qty 3, flat); M2 × 4 mm for speaker (qty 5, flat); M2 × 4 mm for unspecified (qty 2, flat); M2.5 × 4 mm for optical drive (qty 4, flat); M2.5 × 6 mm for display (qty 4, flat,pan); M2.5 × 6 mm for heat sink (qty 2, flat); M2.5 × 6 mm for palm rest (qty 1, flat); M2.5 × 6 mm for system board (qty 3, pan); M2.5 × 6 mm for unspecified (qty 3, pan); M3 × 5 mm for hard driv.
- How long are the screws in Lenovo ThinkPad 390?
- The records range from 4 to 18 mm depending on the position, so match each screw to its own hole.
- What is the thread pitch of an M2 screw?
- 0.4 mm (coarse), which is the standard pitch for M2 machine screws; a 0.25 mm fine pitch exists but is uncommon. The tap drill is 1.6 mm and the normal clearance hole is 2.4 mm.
- What screwdriver do I need for Lenovo ThinkPad 390?
- The sources do not name the drive. For M2, Phillips heads normally take PH0 and Torx heads T6; socket heads take a 1.5 mm hex key.
- Can I use an imperial screw instead of M2?
- No. Imperial look-alike: #2-56 UNC (2.18 mm) is close but not interchangeable. Use a true M2 screw so it does not cross-thread or strip the hole.
- Where can I buy replacement screws for Lenovo ThinkPad 390?
- TechSpareWarehouse (our own store) lists M2 x 4mm, M2.5 x 4mm and M2.5 x 6mm, which match lengths in the records above.


