SOMEONE PLEASE TELL ME!

Will someone tell me what the little "thing" that flips out is on the new cover truck right behind the drivers door? I know everyones seen this truck a million times and whenever i see it i ALWAYS wonder what the hell it is! ...and as you can see, my brokeass has got the good 'ol FREE membership...so even if it DOES say what it is in the mag, I WOULDNT KNOW!