Push Button 28mm Arcade A4 Happ-Style fit0581 You can also compare it

You can also compare it with Pololu Track Set 22T Black - Zumo Chassis Replacement Tracks

USB port indicators: dedicated indicator for each USB port

another is GPIO lid

terminal C is the button signal output

Push Button 28mm Arcade A4 Happ-Style fit0581 You can also compare itHapp style 28mm arcade button rated for over 5 million presses. Built for gaming machines, pisonet, pisowifi, and karaoke setups that see heavy daily use. The switch socket clips in securely so it won't fall off, and the whole button pops apart for easy install and maintenance. Specs Button diameter 28mm Outer case diameter 34. 8mm Total length 61. 51mm Material Plastic Rated life Over 5,000,000 presses Colors Green, red, yellow, blue