grnamin
Enlightened
This is probably old news to you all. If you pluck out the foam in the plastic box your flashlight came in, you may find a USB light that Yitsan included in a small ziploc type baggie. Make sure you plug it in with the LEDs facing away from you. They are very bright! 
I would never have known, I removed the bottom one and seen the spare o-ring and screws but didn't think to remove the upper one, so cool :thumbsup:.
