Locking Knob (C900 and C1200 Series) Manufacturer HAYWARD POOL PRODUCTS, INC. Manufacturer Number CX900G Other Products Using This Part: C9002 Star-Clear Plus 90 sqft Cartridge Filter C12002 Star-Clear Plus 120 sqft Cartridge Filter C1200 Star-Clear Plus 120 sqft cartridge Filter C12002S Star-clear Plus 120 sqft Cartridge Filter C751 Star-Clear Plus 75 sqft cartridge filter. C9002S Star-Clear 90 sqft Cartridge Filter C900 Star-Clear Plus 90 sqft Cartridge Filter C7512 Star-Clear Plus 75 sqft Cartridge Filter