BN-LINK 7 Day Heavy Duty Digital Programmable Timer - Dual Outlet 2 Pack can control your system every day, every several days, or several times per day! The timer allows up to 8 on/off times per day, a one (1) minute minimum "on" time, and different settings for different days. The timer is a great way to keep everything on track and promote the healthy growth of your plants and flowers. It's three-prong grounded, has an LCD digital display for easy operation, includes a battery backup, and has a dual outlet feature so you don't lose a plug. These timers are great for lights or hydroponic systems. Using timers to automate your hydroponic garden adds convenience and encourages productive growth of your plant. Timers allow you to provide a consistent light, nutrient, and airflow program for your garden. The battery backup assures you stay on schedule even after a power outage. Our product has an internal battery that will last 3 months when not plugged into an electrical source. If the battery needs to be recharged, plug it into an electrical source and allow it to charge for 30-45 minutes. After the timer has been fully charged, use a small pin to push the small reset button to turn on the display. Please follow these instructions for the timer to follow the program after setting the schedule. (a) If you want the timer to be currently ON and follow the schedule, press the ON/AUTO/OFF button so ON is shown. Then press the same button once so AUTO is displayed (b) If you want the timer to be currently OFF and follow the schedule, press the ON/AUTO/OFF button so OFF is shown. Then press the same button once so AUTO is displayed. If you have any question, please contact us: Support@BN-LINK.com