This is Xlab's second generation of daytime training strobes specifically designed to fit on aero seat posts and aero section cowhorns of tri bikes. The front light has three different modes - hi-beam, low-beam and flashing. Flashing mode is recommended for daytime training. The rear light also has three modes - constant, both flashing, alternate lenses flashing. Xlab recommends the alternating flashing mode for daytime training. Runtime for the front is flashing up to 17 hours, hi-beam up to 6 hours, low-beam up to 12 hours Runtime for the rear light is alternate up to 124 hours, constant up to 4 hours and flashing up to 21 hours.
Each light is secured in place with two O rings. In addition wider flat rings are provided for wider seat posts and aerobars. If you want to leave the light mounts on for a long period of time then two zip ties are provided. The lights are easy to use. Each light is easily unclipped from mounts for battery changing and the on mode button is conveniently located on front of lights. Includes two AAA batteries per light.