This is an upgradeable accessory to the 100L BrewZilla Generation 4 only.

It has been pressed into a slight concave shape to match the curvature of the boiler false bottom of the 100L BrewZilla Gen 4. It also includes a longer Eye Bolt assembly with a wing nut.
The order of bolt to washer to nuts goes as follows. Eye bolt, washer, false bottom, washer, nut, HED then wing nut. This is so that the eye bolt does not come completely removed when and if you clean underneath the Heat Exchanger Dish.

What does it do?
Due to the concave bottom and central draining hole, the wort being recirculated through the pump will pass through the malt pipe and then down through the boiler false bottom. The wort would normally then follow the path of least resistance, making a b-line for that drainage hole.
What this Heat Exchanger Dish does is force that recirculating wort up to the edge of the BrewZilla base and pass over the elements for a longer period, this then aids in faster heating exchange with the wort, which can help you on a brew day reach those temperatures much quicker.