From the product page on Amazon.com:
List Price: $129.99
Price: $34.99 & FREE Shipping on orders over $35
I received this product for review.
The light itself is good but not outstanding. I could not identify the brand and model of the LED itself but it does not appear to be a brand I'm familiar with. The Amazon description claims 300 lumens which seems about right (if powered by AAAs). I was pleasantly surprised to see that the light at the brightest setting is not high frequency pulsed but is steady on. I appreciate this as pulsed lights can give some people headaches. The dim setting does pulse (approximately 90 Hz).
The light is powered by either 3x standard AAA (clipped together in a magazine) or a single 18650. The AAAs at combined 4.5V resulted in a brighter light than the 3.7V 18650. It is controlled by a single push button on the back. Click it on and then a half-click will switch between modes: High, Low, and Flashing. The light can also be focused between flood and spotlight. While the spotlight is considerably brighter than any single point in the flood light, less overall light is projected.
Explanation: These kinds of lights focus by moving a lens forward or backward. When it is pulled backward (against the LED) almost all of the light from the LED goes unfocused through the lens resulting in a wide flood light. When you pull the lens forward, focusing the light from the LED, most of the light is lost against the sides of the case. The light that does hit the lens is focused on the target resulting in a brighter patch at the cost of much of the LED light output. You can easily prove it by shining one of these lights in a dark room at a white wall. The room is noticeably brighter at flood, dimmer at spot even though the spotlight is brighter where it hits.
The 18650 battery is interesting. I found them here: http://www.amazon.com/Integrated-USB-Charger-18650-Battery/dp/B00PN9LVU6. The 1300 mAh capacity is about half what you'd expect from a typical 18650, but that makes sense considering the power lost to the USB cap and charging circuit. I was pleased to note that the USB recharge port only has power pins, no data pins. As a rule I don't plug any USB device into my PC without protection. Important, see Every USB Device Under Threat. New Hack Is Undetectable And Unfixable which, happily, does not apply to this device).
The batteries charged as expected. I appreciated the LEDs to indicate charge status. The patent listed on these batteries is not registered to this product but to a similar NiMH USB rechargeable AA battery.
The two tail lights are of different quality. One is quite bright while the other hardly works. The two CR2032 batteries in each were equally charged so that was not the root cause. I'm actually very pleased with the bright one. It may find use as a camping light to preserve night vision instead of being mounted to my bike.
The mounting hardware is unremarkable. It does the job as expected and kept the flashlight in place reasonably well. I appreciated the thumb screw used to attach the quick release mounting bracket to the seat post (instead of having to go find an Allen wrench).