Fill in those unwanted gaps in the bottom of your wave board. You find that even loose fitting blankers will get salted up and seem to be quite hard to remove, rinse the box with clean water if possible. The slot box blankers have an angled bottom so that you can push one end down to lever them out. All sold as pairs. Available in yellow or black from recycled material
To keep your K4fins looking clean and shiny it does them no harm at all to go in the dish washer every now and then. This is highly recommended.
Minor nicks and scrapes can be easily sanded out with 240 or 400 wet and dry.
Major damage can be trimmed or scraped smooth with a sharp knife.