they are not necessary, you can will notice no ill effects if you drive without them. you can retap them if you have broken them. if you like member RonJ will chime in with the same info, if you use the search feature using "95 civic ex rotor screw" you can find this topic discussed a few times in the past, and i believe in depth in 2010, google will give you that thread first. best of luck to you on your modding adventure, can i help you more?