Screws are not included-- the ones you have in your current light switch plate will translate well. If you would prefer new screws, let me know, and I'll get some 'on the cheap'. LOL
All of my light switch plates and electrical outlet covers are sealed with 4 (or more) layers of matte finish sealant, and are more than capable of surviving typical use. You prolly don't wanna take a bath with them though. Just saying.