Heres a before and after with my spider plant. The timer function is right on.

The clamp is strong and holds lights in place. They seem to be helpful for my window-based tomato plant seedlings on cloudy days. Now a couple weeks of using lights has the plants looking healthier.

Only one of the three lights work. It shuts itself off and won't turn back on unless it is unplugged and plugged back in. My 2 big complaints are that these don't automatically come back on if you use an external timer and only one of them worked out ...  Read More

The light is smaller in size id hoped for but it's a 1000w! This light is extremely sturdy. The knob is not flimsy.