Small, convenient, well built.
About says it all doesn't it?
The light is about the size of a cigarette light in your car (if your car still has one of those). The multiple light modes are handy and all seem to work very well. The light mounted easily to my seat post under my saddle bag and has stayed secure even on poorly maintained city roads.
The built in male USB plug makes charging a breeze - no need to remember where you put the cable. Charging port is well protected when the rear cap is on.