This Hoover Primary Filter fits just behind the paper bag in their Spirit series canisters. This white electrostatic filter pad is 4 11/16" in diameter and 1/16" thick.

If you have a later Hoover canister, then you need the Canister Primary Filter. If you have a Hoover Dimention Canister, then you need the Dimention Primary Filter. For similar products see our list of Hoover Vacuum Supplies.