Carrying a BSA Hot Spark as part of one's EDC seems like a great idea. Doesn't it get pretty beat up on your keychain though?
I slipped a small section of aquarium air tubing over mine. I'm not at all concerned about wear & tear and did it primarily to reduce "jingling" but I suppose the protection is a fringe benefit.
I put a little shrink tubing over mine. You can see it here in the top right.
I've carried it like this for at least three years with no ill effects that I can see.