This is a hop-stopper from http://www.theelectricbrewery.com/hop-stopper
. Cost to buy new shipped is $76.50. Asking $61.50 shipped lower 48.
This is a pic inside a 10 gallon Blich.
Below is a pic out of the pot.
This unit is specifically designed for a 10-30 gallon Blichmann brew kettle and requires removing the collar from the diptube and installing it on the hop-stopper.