You've probably seen reﬂective rucksack covers – well, this is a rucksack lighting harness. Those three big ‘lights’ – two at the front, one at the rear – are solar panels.
The actual LED lights are two dots on the side of each panel: white ones at the front, red at the rear. Four hours of bright sunshine – or lots more electric lighting – provides enough juice for around seven hours of ﬂashing.
While Scotchlite is more effective at showing up in car headlights at night, these ﬂashing LEDs are conspicuous in dim light. They’re not bright enough to use instead of lights, but this is a clever way to enhance your visibility. If you’re concerned about weighty matters, the Baglite adds 246g.