What is the problem ? open them and delete them , you will see answers to your questions very fast This must be a highly guarded secret. I've asked around several times and... Nothing. to who did you ask this question ? what secret are you talking about ? Keep in mind that the foam you will buy should resist to any lube products you will use in these switches . There is no secret here . Very simple . Quality of the contacts inside these switches is also very important but you don't talk about them .... The foam is used only to avoid the knob to move . No other reason .