Fits Riccar canister vacuum models 1800 & 1700 canister vacuum cleaners using Riccar HEPA & Charcoal filter part RF17. Riccar RF-17 HEPA & Charcoal Canister vacuum cleaner Will Also fit Simplicity full size canister models. Package contains 1 high efficiency HEPA Filter, and 1 Pre-motor charcoal filter in each box. These filters should be replaced once every year.