I've worn this light-weight vest twice while riding my bicycle. Both occasions were when I was caught out unexpectedly at night on the bike. I was supremely happy to have the vest on both times as drivers in this area are not bike-friendly. (A pedestrian called out "No one's going to hit you!") I don't know how well the lights will hold up in the rain. There is not indication on the package whether these Christmas-tree like lights are equivalent to outdoor lights or lights intended for the indoor tree only. The vest includes a pocket that can be used for a cell phone also. The vest is so light-weight that I am wary of using it for that purpose; others might disagree.