The design of the exterior of the sleeve (2) prevents a second suction hose from lying in a sealing manner against the sleeve (2).
所述套管（2）具有外部的表面构造，所述表面构造防止第二抽吸软管以密封的方式紧贴在所述套管（2）上。
2
It is an integral entity which is made up of a manual corrugated pipe or sleeve piston pump and a flow controlling valve. It is suitable for liquid suction, pressing and siphoning.