Electrical:Butyl sealant tape can be employed to seal and insulate electrical connections and cable joints, to help prevent the ingress of water and other contaminants.
Flex Tape The Ultimate Waterproof Solution

self bonding rubber tape. Simply stretch the tape around the object, overlapping the layers to ensure a tight seal, and the adhesive properties of the tape will bond to itself, creating a strong, durable connection. The tape can be easily cut to size with scissors or a knife, making it customizable for any application.