As with most Knog products, the Blinder Arc 5.5 is creatively named and stylishly finished. Its 550 lumens are used very well providing a strong wide beam of light that reaches out to 25m (three seconds of vision at 30kph).
Peripheral vision is very good with the Blinder; the wide beam spreads out very well to each side of the road. Its lens is shaped to flatten the beam to an elliptical 16? vertical and 24? horizontal profile to minimise the glare experienced by oncoming traffic. It's water and dustproof (IP68 rated) and secured by a stretchy silicone strap. It is slightly nose heavy and on my bars had a tendency to tip down over time. There is no tightening mechanism in the mount once it is latched, but this could be resolved by a couple of wraps of PVC tape on the bars for extra girth.