David Hasselhoff is auctioning off some items from his personal archive next month ... including a creepy model of himself that was used in the 2004 "SpongeBob SquarePants" movie, his personal KITT car, a KITT golf cart, and some of his clothes.

SEE THE AUCTION HERE

Here's a gallery of all the items.  And here's video of the scene from the "SpongeBob" movie, which used the model.