One difference I see between the SafeRide light and the ActiveRide light is that the ActiveRide light has an external wire coming out of it, suggesting an external power source. However, their webpage has no documentation of that. No statements of how many cells in it and no statements of any change in size of the ActiveRide light housing. It could be a recharge wire too I suppose.
http://www.philips.co.uk/c/front%20b...ONSUMER%3Dtrue

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