Walk Behind Lawn Mowers

Hi - We just bought an LC221RH mower from Lowes yesterday and as I unpacked it today a bolt fell from somewhere into the bottom of the box. It fell when I was lifting / unfolding the handle into place. I've looked and looked and cannot find where this bolt is supposed to go (or if it even belongs on my mower or is it an extra that just ended up with mine?). It's black and the head is 1/2", and the threads are 5/8" long. Any clue?