Test it out before you trust the seal!
I leaked two full bottles of pumped milk my first day using these discs, which was frustrating because of the lost milk and the mess! The disc goes into the bottle top and looks like it should press all the way up through the hole. My husband and I (both mechanical engineers) made the same mistake assuming that was all we had to do. Once the lid is on the bottle, you need to push the sealing disc down toward the bottle to obtain a seal. Otherwise it leaks. Test it out with water to understand how the seal works before using it with precious breastmilk!
20 November 2012
Works as expected
Works great to seal off breastmilk. Also it's easy to write the date and time on the disc with a wet erase marker and it doesn't come off as easily as if you write it on the bottle itself.
24 October 2012