The sole has a slight arch making them more comfortable than your average flat shoe. Purchased this item mid December 2019, it stopped working on a trip to Florida in late fabruary 2020. Honestly for after pregnancy esp with a c section for the following weeks when you bleed, these were amazing. The mounting part (that holds your phone) is made of plastic, for the price, I guess most of it went into the metal clamp that goes on the handlebars. Oh and they are marked R or L so make sure they are in the correct ear I highly recommend this product (not something I do often). And the case has great detail! The Onyx Studio 4?s audio quality is right up there in a close 2nd place to the 5, but it?s currently more expensive. La única razón que no le doy 5 estrellas es porque no permite abrir completamente el case de los audífonos y por lo tanto dificulta un poco la tarea de sacarlos, fuera de eso todo perfecto. Wouldn?t buy again or recommend.