Although some urban cyclists may think that bike bells are fussy and unnecessary, those of us who use them will tell you that they're much easier and less confrontational than yelling "On your left!" at pedestrians. Well, the Runbell is designed to let runners in on the bell action.

The Runbell's grip is made from brass-electroplated aluminum, while the bell itself is solid brass. The whole thing weighs in at around one ounce (30 g), and is worn on the index and middle fingers like ... well, like a partial set of brass knuckles. The spring-mounted striking mechanism is operated by the thumb, and silicone sizing inserts are included that can be removed for use with gloves.

Will runners wonder how they ever made do without it? Probably not, although if you've ever been surprised by a runner suddenly passing you from behind on a sidewalk or trail, you can probably at least see its attraction – and flipping your thumb is certainly preferable to shouting at walkers' backs repeatedly.

Tokyo-based entrepreneur Kevin John Nadolny is currently raising production funds for the Runbell, on Kickstarter. A pledge of US$25 will get you one, when and if they're ready to go.

You can hear what the bell sounds like, in the pitch video below.

Sources: Runbell, Kickstarter