5 inch would definitely not be heavy enough. The case is nice, straight forward, indicator lights to let you know if the earbuds and the case are charging. And causing it to slide down. i would advice sizing up at least half or one full. They are cute and I was OK with the design only lasting a few weeks (i brought similar flops a few years ago and the design faded immediately). The construction so far appears solid too. Denver to Oregon and back. Solo llevo una semana con ellas pero ya fui a escalar (rock-climbing) a la montaña y son súper cómodas para cambiarse de zapatos rápidamente. but they fit and look great! The title should say it all, but I’ll say more.