Embarrassed a couple of times with a wagon and drag using an ERF prime mover.Backed into towing hitch.Standing between both I put on the red line and the thing started rolling downhill.Obviously pulled redline back off within a couple of feet.I realised that the handbrake lever on the dash didn’t appear to a heavy handed me to be seated deep enough in a small depression at the base of the lever.I had a habit of trailing my fingers over it as I let go which was enough to release the brake again.No harm done fortunately.