Once installed, there is minimal on-going maintenance required for your Smarti systems. Our valve contains a green crystal enzyme Key Ring which dissolves over time, lasting for approximately 16,000 uses – equivalent to approximately 3 – 4 months of standard usage. When the ring changes colour to become completely clear, it is depleted and it is time to change the cartridge, which is easy and contact- free using our unique and hygienic key change system.