You may have seen him on YouTube or Letterman, but if not, he now has a book. Gar Ryness is the “Batting Stance Guy,” whose ability to mimic the batting stance of any baseball player he’s ever seen has earned him a place in the baseball universe (somewhere between Uranus and Pluto, if Pluto still existed, but he’s there).

The book is called: “Batting Stance Guy: A Love Letter to Baseball,” and is co-authored with his L.A. neighbor, Caleb Dewart, the dude who has shot the video of Ryness imitating his favorites with a Whiffle bat.

“I’m not a baseball expert or an authority with any kind of credentials other than my unfettered love of the game,’’ he writes. ‘I hope that this book sits somewhere on the shelf between a Bill James abstract and the ramblings of a madman.’’

The man has a sense of humor, but more important, he has an uncanny eye and unfailing appreciation for the nuances of the game, which he expresses with his faithful renderings of some of the game’s most distinctive stances.

Kevin Youkilis is his first entry, and I think Sox fans will enjoy what he has to say.

“To me, he is everything,’’ Ryness writes. “If the batting stance is art, then he is Michelangelo. ... There isn’t a more requested player on the planet than Youkilis.’’

Then he suggests you go out in the backyard with your favorite Whiffle ball bat and try being Youkilis:

Trust me, it will get you nowhere. Seriously -- try it. Here’s what you need to do:

1. Spread your hands about a mile apart on the bat.

2. Don’t actually hold the bat with your right hand. But instead move your right hand up and down the bat like you’re petting a cat.

3. Hold the bat above your head and aim the head of the bat at the pitcher like Julio Franco used to do.

4. Shimmy and bounce like you’re on “Dancing With the Stars.’’

5. Keep your feet together like you’re standing on top of a telephone pole.

6. Run a garden hose up your back and duct tape it to the top of your head. Turn the hose on so water runs down your face and off the tip of your nose.

7. Staple a ferret to your chin.

If you can do all that and make contact with your mom’s best stuff, I’d be shocked. How about doing all that and trying to hit Justin Verlander’s 100 mile-an-hour fastball or Tim Lincecum’s curveball? Impossible.

Check out his impression on Youk in the YouTube clip below, at 1:52: