It seems rather strange that the bicycle doesn’t come equipped with the basic accessories that motorbikes do. For example a brake (tail) light, indicators, or even rear view mirrors. Even with the relatively slower speeds of bicycles, compared to motorbikes, accidents do occur and can be pretty ugly.
Here’s the RearViz, your hand-mounted convex rear view mirror that allows you to look behind you. It comes flat-packed, and can open out to reveal the mirror and even adjust in 360° to point wherever you want it. The Velcro fastener means one size fits all, and the curved mirror gives you a pretty wide-angle view of what’s behind you so you don’t have to turn to look around and risk having a bad encounter. Just remember, objects in the mirror are closer than they appear!