I have several solar drip systems like this, and I like them. Really cuts down on tending to watering for my container plants, and keeps them watered when I go out of town. There's a lot of brands on Amazon, but I like the Srygery brand the best mainly because the interval and duration of watering is fairly flexible for my needs.
***Be sure to keep your water container filled! It's important to install and test your system so you know exactly how much water it uses, especially if you are leaving it while you are away from home. The more often you run it, the quicker your water container will empty.