What can be used to replace the sucker duckbill valve if it falls off

There is no substitute. Each part of the breast pump has its role, the duckbill valve has an impact on the suction. Even if the breast pump is not installed properly when installed, it will affect the suction power. If the duckbill valve is missing or has wear and tear, then there will be no suction and you will not be able to suckle the breastmilk. There is no substitute but to construct a new duckbill valve online. The valve is used for a long time, after countless times of opening and closing and high temperature disinfection will make the silicone aging and deformation, you can buy more than one spare.