Dennis,
The pin is @ 10" long and @ 3/16" dia with one end turned down to a reduced diameter that fits the hole in the inner sleeve of the airbrake as well as the water caps. The length helps insure that you don't inadvertently leave it in the hole as it crosses much of the instrument panel when inserted. This pin and the alignment pin that helps bring the wings in the last 1/2" should have come with the glider. My trailer has a dedicated place for these tools inside on the left rear rail.