This commercial restaurant timer need 110v power supply for use. Save your batteries. This timer is loud to catch your attention even on noisy restaurant kitchen. It is perfect if you need it really loud. If you want it quiet,sound volume is adjustable. When you program this timer at first time , you may feel a bit hard to figure it out. Because there are mutiple functions in one button. Once you figure it out, you will find it easy to program. For example, "INCREASE" button to increase the alarm volume or time digit. Key Features -4 timer windows can be set independently at the same time. This allow you to time 4 different events at once -It is easy to switch Minutes:Seconds or Hours:Minutes Mode -Easy-to-read digit display and comfortable buttons -High decibel buzzer alarm designed for busy kitchen. You can hear the sound even in other room -Remember last setting, easy to recall -Stainless steel construction.Easy to clean and maintain -This timer has two holders. It can be mounted to the wall. It can't be stick to refrigerator because it is 1.54lb All you have to do is plug it in, set your time channels and start cooking Specifications Input voltage: AC 110v Low power consumption: 3W Power cable: 1.5m/59inch power cable with US plug Product size: 170*130*40mm/ 6.7*5.1*1.57inchProduct weight: 700g/1.54lb How buttons work?TIME button: Set the total cooking time. If time ends,alarm appearsREMINDER button: Set the reminder. Before total cooking time ends,you can set a reminder. Reminder will ring before total time ends.If you don't want a reminder, please set it to 00:00DECREASE button: Decrease time digit or volumeINCREASE button: Increase time digit or volumeNUMBER KEY button: Start or stop the time What's in the box 1x Digital Kitchen Timer 1x User Guide