Rear Bike Lights
Rear bike lights can be a life saver. Buy two, there small (one on your back and one for the bike).
Although there are some expensive options out there, the $15 options work great (maybe better) than the fancy jobs. Cateye makes a dozen varieties.
My all time favorite rear bike light is the Cateye TL-LD260 and run for 160 hours (which is good, since I don't really think about changing the battery that often!). Most importantly, it's small, which is pretty key when you have a bike rack, towing leash and rear bike light competing for space on my seat post. Note, however, this light doesn't throw out allot of light from its single LED.
Because the LD-260 doesn't throw much light, we're also using the newest addition to the Cateye line -- the ultra bright LD1000. When riding anywhere that I'm worried about being hit by a car, this is my go to light. The LD1000 is a bit heavier than other lights, and gets 100 hours of blinking our of two AA batteries and cost around $30. The biggest drawbacks, however, is the size on the post -- about the size of a D battery. (It won't fit on my bike when I have the rack on as well.)
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