Exposure pioneered high powered self contained bike lights, and this is the ninth generation of its original ultralight Joystick.
Circular mid range coverage is OK, though there's little peripheral and less punch than with other similarly priced lights, but where Exposure has always scored is on features. The output menus are programmable, with run times for each setting engraved on the case for easy reference plus a power mode indicating backlight in the switch. Battery life is good for the tiny size too, though you’ll soon realise the red warning and flash mode comes on relatively early.
If you need more juice, the 'Smart Port Technology’ socket on the back lets you add piggyback batteries, remote switches and even a mini back light. The simple red rubber band mount works well on most bars – including less extreme aero bars with a bit of ingenuity – and the 'candlestick' helmet mount is brilliant.