When you buy these flea collars they're big enough to fit huge dogs. We've got two small dogs, so I designed this to save on wastage of the trimmed collar.Designed for: "Exelpet Fleaban water resistant 5 month flea collar for dogs"All Excelpet branding property of Exelpet Australia: www.exelpet.com.auCut the collar to fit the bigger dog, then print one of these. I used 0.2mm layer height. Drill a 3mm hole about 5mm from the end of the buckle-less piece, and use a 3mm pop rivet to attach the printed piece to the collar. Make sure the smooth, domed side of the rivet is on the inside so as to not irritate the dog, like the factory-produced buckle.