Some of them, ex Telecom, have been repaired with what looks to be a bitumen compound and then duct taped. I've tried a waterproofing bitumous tape (Norton Flash-Tac) but it's getting through still. This stuff is good but needs to warm up (eg. metal roofs) to work well. Any other suggestions? I'm just concerned about using anything that may attack the plastic. From the MSDS the jar is SAN and the lid may be PE, according to Exide's tech they're both ABS.