The shower cartridge is made of plastic structure, durable, strong, clean and effective This RP46074 Monitor shower cartridge keeps water temperature within a safe ±3.6° F (±2° C), helping to protect you from sudden changes in hot or cold water pressure. Easy to install and repair the leaking faucet Fits all Delta single-handle Monitor 13/14 Series tub/showers,provides temperature control which keeps water temperature within a safe range. Note: Please clean all the contaminants around the previous ink cartridge area when insert a new ink cartridge. Delta RP46074 Shower Valve Cartridge For Tub/Shower Valves 13/14 Series, Delta Shower Valve Replacement-Single Function Temperature Control Valve Cartridge