Today we reach a milestone. This is the 300th time Neatorama has collaborated with the What Is It? blog to bring you the What Is It? game! A big thanks to the What is It? blog for providing such great pictures every week, and filling us in on so many objects we've learned about.

Do you know what the object in this picture is? It doesn't really matter if you do, because we are looking for the funniest guesses. You can win a t-shirt from the NeatoShop! But first, read the rules:

Place your guess in the comment section below. One guess per comment, please, though you can enter as many as you'd like. Post no URLs or weblinks, as doing so will forfeit your entry. Two winners who submit funny and/or clever (albeit ultimately wrong) answers will each win a T-shirt from the NeatoShop.

Please write your T-shirt selection alongside your guess. If you don't include a selection, you forfeit the prize, okay? May we suggest the Science T-Shirt, Funny T-Shirt and Artist-Designed T-Shirts?

There is another picture of the whatisit item at the What Is It? Blog. Good luck!

Update: the mystery object is an 1801 rounding plane; it was used for preparing the ends of wooden axles. But that's not nearly as funny as our comments! Colshorts said "That's a "Pirate Pete's Leg Pointer". Used exclusively at Pirate Pete's custom shops. Remember mateys..."Come to Pirate Pete's, where the prices can't be beat, and you don't have to have two feets".....Arrrrrrrrrrrrrrrr" Yeah, that's worth a t-shirt! The other winning answer came from tarnation, who said "It's a Reverence Shaver 1. Insert arm 2. Have a friend grasp the handles and turn 3. Hang your head while your (now former) friend teases you for agreeing to something so ridiculous." Ha! You really should read all the comments, because they're all good! See the answers to all the mystery items this week at the What Is It? blog.