The Claber 8423 Aquauno Select is a one-way automatic water timer with 63 pre-set programs (+ off and 5-minute test). It is easy to program using two dials: one for the time and one for the frequency. It is battery-operated, so no electrical connections are required; one 9V alkaline battery can power the unit for an entire season. To use the Claber 8423 water timer, screw it onto your outdoor tap and connect it to your hosepipe or irrigation system. Then, programme the timer to water your plants at the desired times and for the desired duration. The Claber 8423 is a great way to save time and water in your garden and ensure that your plants are always properly watered, even when you are on holiday or busy with other things.