The Blaze 2 Watt is is twice as bright as the 1 Watt and four times as bright as the half Watt.  Put this light on your handlebar or helmet and operate it in a low or high mode, it will fit on bars 25.4mm to 31.8mm.  It's bracket mount makes adjustment easy and without tools.  Up to 15 hours of run time on two AA batteries (included).  By the way, did we mention the flashing mode is visible in daylight; yes, when we told you about the 1Watt.