This is a 3 switch control box that incorporates inexpensive single pole single throw micro (3.5mm by 7mm) momentary switches. This part is used for providing left, right, and select input for a stepper motor controlled by an Arduino or Node MCU. You can see how to assemble the box in the files. Not shown is the wiring. The hole in the box is designed to take Ethernet cable (Cat 5, etc) which brings in 4 twisted pairs of 24 AWG wire. You solder 3 of the pairs to the switches (there are small metal tabs on either side that are connected when the switch button is pressed). You'll have a spare pair of wires when done.

I ordered the switches from here: https://www.amazon.com/Uxcell-Momentary-Button-Tactile-Switch/dp/B00E6QJRT4 but they are available elsewhere (http://www.uxcell.com/pcs-7mm-35mm-spst-pins-momentary-push-button-smd-smt-tactile-tact-switch-p-412051.html).