I'm selling these because I bought them but never had a chance to wear them. This is a rare color that's no longer available. The following is quoted from the official website: The GEL-SONOMA 15-50 was created with the outdoors in mind. Inspired by the upper of the cross-country spike "15-50," it's designed for competitive runners who run on various terrains. It has been updated to balance both urban and outdoor use. The tooling incorporates design elements from the original GEL-SONOMA models. It provides excellent cushioning and traction in various environments, from lifestyle settings to hiking.