The S-Click HNS420TM is a 2-in-1 programmable timer switch that automatically turns lights or small heaters off after a pre-set time has elapsed. Time delay can be set in hour increments from 1 to 24 hours - perfect for areas that need to be lit for extended periods and for heated appliances like towel rails. Supporting both timer and non-timer functions, this unit also allows for lights and appliances to be manually turned off with a quick tap. Our hour timer switch is ideal for domestic use and can be retrofitted to most installed lights. An amber LED indicates device status and gives an expiry warning before time-out. The timer settings are retained even after loss of power and can be configured to power up on or off after loss of mains power. Programming your chosen off time couldn't be simpler. A sustained 10 second press of the button enters programming mode. Just tap the button once for each hour of run time you require, up to 24 hours. Programming mode expires 10 seconds after the last tap, and the unit then commits your settings to memory. If you happen to press the button more than 24 times, the maximum run time of 24 hours will be stored. The HNS420TM is also equipped with Boost Mode, a convenient bonus feature that allows users to double the program run time (up to the maximum 24 hours). Instead of a quick tap, a sustained two second press of the button will initiate boost mode and the timer program will be automatically extended; for example, a 2-hour program would be extended to 4 hours.