Cobb question

/r/WRX is a place for Subaru fanatics to show off their rides, discuss modifications, mechanical issues, industry news, and more. It is not a place to buy/sell/trade or spread negativity/hate. Please read the rules, they will be enforced.
I have been driving my 21 base for 2 years now, just realized you can do this!

/r/WRX is a place for Subaru fanatics to show off their rides, discuss modifications, mechanical issues, industry news, and more. It is not a place to buy/sell/trade or spread negativity/hate. Please read the rules, they will be enforced.
Not sure what this thing is. Looks like a molten iron casting pot maybe?

For the identification of mysterious objects