The utility model discloses a III sleeves of CP, barrel including vertical setting, barrel upper end opening part is equipped with the elasticity closing door that can open or close it, is receiving under the decurrent exogenic action, elasticity closing door overcomes self elasticity and opens, and after cancelling decurrent external force, it is automatic closed under self spring action. Throughsetting up elasticity closing door for it opens the convenience, and can self -closing, and its simple structure can avoid in granule nature impurity falls into it, simultaneously to a certain extentcan rain -proof water, and can prevent frostbite winter.