NSeal™ seam tape is an iron-on tape that provides a waterproof and long lasting finish to sewn or welded seams of Neoprene, Lycra, and a wide variety of similar materials.
Covering the seam tape with a piece of paper is a good technique that will help shield and protect your iron and the tape. Preheat your iron which should be set to "silk" or the lowest steam temperature without actually using the steam. Press the iron down with firm, even pressure for 10 seconds. Lift and rotate iron; apply for another 10 seconds. Allow the bond to cool for a few minutes before testing adhesion. After the seam tape cools, check for any loose edges and use the iron again if necessary.
Seam tape provides additional strength to the seam and stretches in every direction to provide a longer lasting bond. Available in black. Seam tape is 20 mm wide (approximately 0.79"). For added seam strength, use Aquaseal®.
The following video on "How to repair a wetsuit" gives some good instructions on different techniques of applying adhesive for neoprene repair as well as a good example of ironing on seam tape.