100% nylon taffeta with polyester mesh lining. Back yoke with mesh venting panel. Contrasting stretch side and back yoke panels. Bungee cord and toggle waist. 3M(TM) Scotchlite(TM) Reflective Material piping and extra wide taping along back yoke. 3M(TM) Scotchlite(TM) Reflective Material graphics on left chest and back.