Digital Watering Hose Timer, Programmable Watering Timer, Automatic Irrigation Hose Faucet Timer Irrigation System Controller for Greenhouse Cooling, Gardening (Red) Start by removing your hose from your faucet outside. Attach the input end of the timer to your faucet and screw it on tightly. Then, attach the hose securely to the output end of the timer. Just set the timer as you'd like, and watch the magic. *Please read the user manual guide completely before use of your hose faucet timer. The great advantage of this hose timer is it is backed by a 1-year warranty. *Depending on the location of the hose's faucet, garden hose types and water pressure, water flow may be slightly restricted. So you must need to have minimum PSI water pressure for the unit to work properly. *This does run on 3 AAA batteries and those are not included with the package,and you have to purchase them separately. A new set of quality batteries lasts up to 6 months that can minimize your cost.