I use this in a water removal vacuum device. Water is sucked off the floor into a bucket, the vacuum keeps the check valve closed. When the vacuum is turn off the bucket drains through the check valve. So it's not meant to be a perfect seal in my case but works very well and does not appear to get stuck.

You'll need an o-ring off a tap/hose fitting and you can use the big washer to seal the other side if needed.

Print the models as they appear in the 3d viewer above, then you won't need any supports.