Firewall adjuster silicone help

Hey guys, I am installing my firewall adjuster and have a question as to what the directions mean when they say "silicone sealant". It says to put a bead of silicone sealant on the back face of the firewall plate (the plate that mounts against the engine bay side of the hole). It also says to use silicone sealant on the inside threads of the lock nut part of the adjuster. My question is what specifically are they referring to when they say silicone sealant?

Thanks for the help!