Genuine 3M Clear Electrical TapeI know there's stuff thats close and maybe cheaper but often leaves residue and doesn’t adhere as well when it gets wet. Great for areas you are trying your best to seal  but don’t waste it on areas you can get by with other. Stuff is hard to find and it's not cheap. BUT, it's the best, IMO. Rattlesnake RC wants to offer you the best.  3M Tape  5. The Original and the best.