Silent Vibrating Travel Alarm Clock with Light for Heavy Sleepers- Hard Plastic Casing, Accuracy Quartz Display, LED Back-light for Night, with Snooze Mode (Black) The Vibrating Alarm Clock comprises a sweep second hand that is completely silent ideal for those who need complete silence to fall asleep. The alarm clock begins with a soft tone which gradually increases in volume over the course of a 30 seconds and then continues until turned off. The snooze allows the alarm to ring every 5 minutes until switched off. Just a quick tap on the clocks top button and the full clock face will illuminate automatically goes off back light after 3 seconds. Button to adjust Up - piano style Middle- the electronic sound style Down - turn off the alarm ring Alarm Clock only a very small current consumption we recommend using carbon batteries alkaline batteries is not recommended