The M4 size of Slotted Terminal Screws is dimensioned by DIN 84. The tables below give the dimensional row from the standard, the drill and spanner sizes that go with it, and the assembly torque per property class. The technical drawing on this page redraws to the exact values selected.
M4 Dimensional Row (DIN 84)
| Thread size | Pitch (mm) | Head diameter dk (mm) | Head height k (mm) | Slot width n (mm) | Slot depth t (mm) | Common material | Common length range (mm) | Reference standard |
|---|---|---|---|---|---|---|---|---|
| M4 | 0.7 | 7.0 | 2.6 | 1.2 | 1.6 | Brass CW614N | 5~35 | DIN 84 |
Spanner & Drive for M4 Slotted Terminal Screws
Drive geometry for M4 Slotted Terminal Screws is given by the row above; match the tool to the listed values.
Hole Sizes for M4
| Coarse-thread pitch (ISO 724) | 0.7 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 4.5 mm |
| Tapping drill, coarse thread | 3.3 mm |
Tightening Torque for M4
| Class 8.8 (dry, ~µ 0.125) | ≈ 2.9 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 4.1 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 4.9 Nm |
Indicative dry-joint values. Lubrication can lower the required torque by 15–25%. Always confirm against the joint design, especially when going up a strength class.
Proof Load & Strength for M4
| Tensile stress area As (ISO 898-1) | 8.78 mm² |
|---|---|
| Proof load, class 8.8 | 5.1 kN |
| Proof load, class 10.9 | 7.3 kN |
| Proof load, class 12.9 | 8.5 kN |
| Min. ultimate tensile, class 8.8 | 7 kN |
Proof load = stress area × proof stress per ISO 898-1. Design joints so the working preload stays below the proof load of the selected class.
M4 Slotted Terminal Screws Weight
A steel M4 slotted terminal screws at the listed 535 mm length weighs approximately 162 g each — about 162 kg per 1,000 pieces. Stainless A2/A4 weighs roughly the same (density 7.9–8.0 g/cm³). Actual weight varies slightly with head form, thread and finish; use this figure for freight estimation only.
Common Applications for M4 Slotted Terminal Screws
M4 Slotted Terminal Screws are commonly specified for electronics, PCB hardware, optical mounts and small-scale machinery.
Installation Tips for M4 Slotted Terminal Screws
- At M4 the joint is sensitive to over-torque — use a torque-limiting driver and check the head doesn't bury into a softer counterpart.
When to Step Up or Down from M4
When the joint preload approaches the proof load of M4 class 8.8, step up to M5 class 8.8 (or move to M4 class 10.9). When the joint is over-specified, M3 often saves weight and cost without losing the safety margin.

