I experienced an annoying delay in completing a mast re-wiring project, just because I couldn't locate a reasonable source for rubber grommets that were the right size. The ones supplied with the Catalina Direct wiring kit had too narrow of a groove to fit the .10" thickness of the mast (and the opening for the 4-strand wire was too small). After numerous sessions on the 'net, I found that McMaster and Carr has a super selection. www.mcmaster.com Although I had to buy a bag of fifty, it was only $8 bucks.