Hi, guys.

I recently bought a Joseph Allen & Sons Non-XLL razor at an antique store. It's in great shape and was even sharp enough to shave with, albeit with a little tugging at my beard--not bad, really. What interests me most is that it has what I've found is called a barber's notch at the point of the blade, but I don't know what purpose that serves. Any info?

Thanks,

Dan