The On Cloudswift 4 AD is designed for a snug, sock-like fit upon first wear, thanks to its bootie construction. Ensure you select your correct UK size for optimal comfort and performance; refer to On Running's sizing chart if unsure. This shoe is primarily compatible with urban environments, including pavements, asphalt, and light park paths. To care for your Cloudswift 4 AD, gently brush off loose dirt after each use. For deeper cleaning, hand wash with mild soap and cold water, avoiding harsh detergents or machine washing which can damage materials. Allow to air dry naturally away from direct heat or sunlight. Avoid submerging the shoes for extended periods. Regularly check the outsole for embedded debris to maintain grip.