Material:ABS,PE,PP,HDPE Anti-shock Light weight,Good strength,Good toughness Petroleum, chemical, power ... , two ribs and three ribs on the top of shell could be doneLock type of back hoop: Turning knob (rachet), Press ... GH060DescriptionSafety helmet with V rib with 6 cooling vents on top of the shellMaterialShell-ABSWeight380gAccessoriesFabric tape, buckle, pinlock, ratchetColourRed, Yellow, ...