KITT has a hidden grappling hook mounted under his front bumper (seen in Season 3 and 4) and another in a compartment behind his tail light plate (seen in Season 1 and 2). Most often the hook is connected by a strong cable, but a metal arm has also been seen.
("Not a Drop to Drink")
The Grappling Hook also had a winch. The button was labeled GRPLG HOOK throughout the show. Oddly enough, in the two-part episode "Goliath Returns" Michael hit a different button during the episodes climax.