I would recommend either Aquaseal (http://www.mcnett.com/Aquaseal-Urethane-Repair-Adhesive-Sealant-P320.aspx) or the Aquaseal Wader Repair Kit (http://www.mcnett.com/Aquaseal-Wader-Repair-Kit-P182.aspx) depending on the type of repair. If the waders are leaking because the seams have become compromised, I would recommend re-sealing the seams with Aquaseal. Begin by turning the waders inside-out. Next, thoroughly clean the seams with a mild abrasive, like 70% isopropyl alcohol (dirt, oils and particulates can interfere with bonding, so the cleaner you can get that surface, the better). It is important that you remove any previous adhesives that may be present. Next, paint a thin layer of Aquaseal along the entire seam overlapping seams edges by at least 1/4". Allow 12 hours to fully cure.
If you have a large hole or tear that requires a backing, you will need the Aquaseal Wader Repair Kit. I would recommend the following: Begin by thoroughly cleaning the outside of the waders where they are damaged. Once clean and dry apply the black fabric patch to the outside of the waders, covering the entire damaged area by at least 1/4''. Next, turn the waders inside-out. Next, clean the inside repair area with the 70% isopropyl alcohol. Once clean and dry, cover the entire hole or tear with Aquaseal and allow 12 hours to fully cure.
The Aquaseal Wader Repair Kit is also ideal for quick, in-field repairs. If I were out in the field and ripped my waders or put a hole in them, I would recommend the following: Begin by cleaning the damaged area as best you can. Once clean and dry, apply the black fabric patch to the outside of the damaged area allowing overlap of repair by at least ¼’’. This will create a dam preventing the Aquaseal from leaking through and will also hide the repair area. Next, turn the waders inside-out. Once again, clean the damaged area as best you can. Next, apply a thin layer of Aquaseal over the damaged area using the brush. Extend at least ¼’’ beyond damaged area. Next, use the clear Tenacious Patch to cover the Aquaseal. NOTE: The patch must extend at least ½’’ beyond the Aquaseal and should bond directly to the wader fabric. This should also prevent the Aquaseal from leaking through the patch and will allow you to use the waders immediately as the Aquaseal cures. Next, turn the waders back out and hit the water!
Once the Aquaseal has cured, you can either leave the patches on or remove them. It is your discretion. Either way, the cured Aquaseal will prevent any water from leaking through.
You can also make instant repairs to pinhole leaks in the field using Aquaseal UV (http://www.mcnett.com/gearaid/aquaseal-uv#10612). Aquaseal UV works on neoprene, GORE-TEX®, and other waterproof breathable fabrics. Clean surfaces with isopropyl alcohol to remove surface residue. Apply Aquaseal UV over hole. Overlap damaged area by at least 1⁄4". Allow 30-45 seconds to cure. Replace cap immediately. Aquaseal UV is great for making instant field repairs to pinhole leaks. Once you get home, however, you will want to make a permanent repair with standard Aquaseal.