Tactile Momentary Switch SPST

Tactile Momentary Switch SPST

This is a tactile momentary switch with single-pole single-throw (SPST) contacts. The contacts are normally open until depressed. The wiring is very simple to deduce using a continuity meter. The height is 4.3 mm, which is just less than 5 mm, and the footprint is 6 mm × 6 mm. These switches are utilised in keyboards for general switch input and are PCB mounted.


Product Name Tactile Momentary Switch
Type Momentary
Dimensions 6 mm × 6 mm × 4.3 mm
Button Size 1.3 mm × 3 mm
Pin Spacing 9 mm × 4 mm
Pin Size 2 mm × 1 mm
Material Plastic, Metal
Colour Black, Silver Tone
Net Weight 13 g


Switch Contacts and Wiring

Inside there are metal strips connecting one end of the terminals to the other end. Even though it is a 4-pin switch you only ever need to connect two terminals, but the extra pins are useful for PCB mounting.


For the replica Sinclair ZX80 project, I decided to use these switches, as the rubber membrane is difficult to find. However, there are firms providing custom membrane keypads, which are extremely cost-effective and can save you from soldering hundreds of these SMD switches.

PCB Mounting

PCB Mount

It fits nicely on my replica ZX80 kit PCB.

SMD Style

This switch is in the SMD style and as a result the terminals are short and exactly the length required for PCB mounting


These switches are available from a wide range of places such as eBay, Amazon, and RS. I managed to buy 50 for £2.50 on eBay and it came all the way from China.