The patented Aqvalock is mounted at the bottom of the urinal. In the Aqvalock there is AqvaLockgel, that acts as non returnable fluid valve blocking odour - not a single drop of water is used! After every three months, AqvaLock needs to be refilled. Refilling of AqvaLock Gel takes only a few minutes.Cost of refilling is just Rs.375/urinal/quarter.