Improved Water Chamber for AirSense 11, HumidAir Water Tub for S11 Series, 340ml Upgraded Humidifier Tub Container,Great-Value CPAP Supplies by Medihealer.

Great product even better than the original. Must buy.

Harder to assemble, leaks like crazy (big water pool under machine the next morning), and too tight a fit into machine, so hard to remove.

Works better than the breathing store model..

works well but hard to get used to having to take top completely off for refills. was concerned about small plastic bits replacing hinge would break - so far they have not. but I am very cautious when removing lid to add water. does not leak, seems to have a good seal.

Inside ports are not correctly positioned for proper air fit with Resmed device (CPAP)

This is an inexpensive replacement and that;s the only good thing about it.It holds less water than the original, it’s hard to take apart and put together. If you are not careful the water leaks.Spread the extra money and get the original.

It leaks and eventually fails. It can be tricky to put together. That's a pain since you have to do so every night. Not certain what the improvement is.

This actually works better than the original product. It seems to be a better fit for the machine.