Rite-Size C fits Penguin 200B, 350B, 330B, and 170B.Rite-Size B fits Penguin 150B, 110B, and 125B.Rite Size C fits Penguin 200B, 350B, 170B, and 330B. Product Features A perfect fit for every filter Meets the highest standards of water purification and operational ease Each cartridge is pre-assembled

Fits all Emperor BIO-Wheel filtration systems. Product Features A perfect fit for every filter Meets the highest standards of water purification and operational ease Each cartridge is pre-assembled

Rite-Size B fits Penguin 150B, 110B, and 125B.Rite-Size B fits Penguin 150B, 110B, and 125B.Rite Size C fits Penguin 200B, 350B, 170B, and 330B. Product Features A perfect fit for every filter Meets the highest standards of water purification and operational ease Each cartridge is pre-assembled