ThinkTank 7 LED Headlamp Water Resistant Light - For Head, Hat Or Helmet, With Elastic Head Strap

It came in a box with no instructions or diagrams, and I can't figure out how to get it open to put in the batteries. There is also no on-off switch that I can find, although I might be able to figure that out if I could get the batteries in. Don't buy this.

Great price, easy to use, bright, no complaints.