A flange is a flat or raised ring-like structure used to connect pipes, valves, or any other equipment together. It provides a strong and tight seal between the connected parts. Full definition
If it does, you might need a different size flange size (usually a larger size if it hurts). (wendywisner.com)
Try the Lansinoh ® Manual Pump, the ONLY manual pump with a unique stimulation and expression mode for more milk in less time, two sizes of flanges for a perfect fit and an ergonomic easy - express handle. (lansinoh.com)
The Milk Genie comes boxed with 3 complete sets of flanges in different sizes (plus Pumpables sells even more sizes) so you don't have to worry about investing money into something that doesn't work for you. (pumpables.co)