Blackburn Mars 4.0 rear light review
With a main one watt LED and two smaller side facing LEDs the Mars 4.0 is one of the best sealed rear lights.
A tool-free removable rear plate covers the batteries, but beyond the battery plate everything is sealed. The power button is part of the secondary seal behind the internal battery tray.
A lifetime warranty and excellent performance are matched by a run time of over 150 hours, and there’s an array of top quality tool-free mounting options.