The Spectra Duckbill Valve Set is designed to increase suction and provide better output during pumping sessions.
If you notice reduced suction when pumping; this is often the first sign that your duckbill valves need to replace. If you are pumping regularly, you should replace your duckbill valves at least every 3 months.
The top of the duckbill valve is quite delicate and can be susceptible to fraying or tiny tears; if you notice reduced suction or lower milk output then examine this area carefully.
Your duckbill valves will last longer if you avoid cleaning them in the dishwasher or sterilizing.