5 was definitely too big. Only down side is since I have pretty thin feet and they are a bit loose on me and that cant be adjusted, unfortunately. When I lost my last set of earbuds I needed a replacement quickly. I would have to unplug it and shut down my iPhone X and reboot in order to get a few extra minutes of a podcast. The nuts, washers, and bolts are numbered by type but the instructions dont even use these numbers. Headphones with a 3. Bought it on the deal. Either way its battery is a dud. I also think they are most comfortable than my other Birkenstock Arizonas, but I think this is probably just me. You sprint back inside and into your game room, knocking over a lamp, two tables, and a whole rack of movies in the process.