Note that there are normally two main types of momentary push button: 1) the "free" ones, that have no outer protection (and that can be thus activated by - sa

Note that there are normally two main types of momentary push button: 1) the "free" ones, that have no outer protection (and that can be thus activated by - say - a slap with a open hand) 2) the "safe" ones, that have an outer rim that prevents the button to be presssed by anything bigger than the actual button diameter (only finger, pencil , etc. will activate it) There is a third one, sometimes called "mushroom push button" that is of the "free" type, even easier to activate. Check this catalog page: https://www.otto-controls.com/products/electromechanical-switches/pushbutton-switches https://www.otto-controls.com/products/electromechanical-swi... once you have chosen the type you want, you will be able to find a similar one by many different manufacturers/retailers.