The canister replacement for the Rena Filstar XP2 external canister filter consists of the outer canister, inner filter baskets and rubber feet. To avoid breaking the canister brackets when attaching and closing the top of the filter to the canister always start with an empty canister and let the aquarium fill the canister. Make sure when replacing the basket assembly that the basket is lined up and nested to each other correctly. Also make sure the basket assembly is seated properly in the bottom of the canister. Failure to do so will result in broken clip(s) or broken bracket(s)on the canister itself.