We have a very busy surf hire business from our shop. With that many wetsuits going out daily in the summer months, added to the way some people treat them, we have to do many repairs! GearAid Iron mend tenacious tape combined with Black Witch is our winning combination and extends the life span of our rental suits greatly.
Neoprene patch is a flexible fabric sheet with an adhesive on the back that is activated by heat. Simply make sure your wetsuit is dry and clean (very important or it won't work!), cut a section of the Iron mend from the sheet and cover with the heat shield paper provided. Set iron to about half heat then Iron in place, one permanent repair. If you get a split in the suit we always glue it together with Black Witch glue first then use Iron mend on the outside of the suit. Perfect repairs every time that last.
In our experience GearAid Neoprene patch will not stick on single lined neoprene (shiny bits as needs the lining for the glue to penetrate into) or areas of very high stretch like a neck opening. All other areas of the suit it's fantastic.
In the tube you get a patch 254mm x 150mm, enough to do many repairs, some heat shield paper to put over to protect the rest of the wetsuit from the iron (always use it!) and full instructions. If you can, practise with it first on an old suit, once you get the hang of it you can make professional repairs every time.