B&M Standlight. Perfect replacement for the incandescent that came with the bike. Said unit had difficult-to-find .6 watt bulbs that were dim, lasted only a month or so, and went out when the bike was not moving. The Standlight is a bright LED device with a capacitor that keeps it let for about ten minutes at a stoplight. There is nothing to burn out, and it is as reliable as rock.

Paul