I have not been into one of those but, I was close to buying a used one based on pictures. From what I could make out, it looks like a metal screen, not a 'filter'. I also have not looked at the rest of the cooling system from that era of machine but, my suspicion is that they took the screen that used to be in the coolant tank and moved it to that canister.
So if you're looking for actual filtration, you're probably better off buying a sock-filter canister. If you just need to remove the bite sized chunks, the Haas might be your answer.