Extremely quiet with no rustling or flapping when your speed increases this is assos39 lightest protection shell for extreme versatility pattern cut and tailored to fit your body in the cycling position with a regular fit to suit all types of rider clicks on and follows your movement packs small and light enough to take with you on every ride just pop it in a jersey pocket ideal protection from the chill on an early summer morning or spring evening or to don before a fast swooping mount