For those that dont know, a winding check butts up against the top grip of the fishing rod handle to make a neat join between the handle material and the butt whipping. They are rarely used on surf rods but are very useful as a finishing touch on boat, carp and spinning rods, though you do need to make sure that you use the correct size; the check should be a fairly good fit to the rod blank otherwise they can be more trouble than they are worth! These nickel plated checks from Seymo have a good finish with no sharp edges to dig into the blank, though I find that it is best to extend the whipping coating over them to ensure they are protected from the saltwater environment. Inside Diameter: 10mm Price per check.