After reading some of the posts about tandems getting hit from the rear we decided to add a light to the rear of our tandem. From what we have read the Dinoette seemed to be a good choice. I placed an order for the 300R on Saturday and it arrived today. I have it mounted and just took it outside in the dark to see what it looked like, I checked it out earlier in the daylight and I am totally impressed, this thing is bright! People should be able to see us in the day and in the night. At $200 it was not cheap but what price can you put on safety. It only weighs 135 grams.