This will not work in zero gravity. There is no flow of ink to the ball.

Try holding a pen upside down and writing with it. It will not work for very long.

TR

I've decided on the desert tan Rite in the Rain 4x6 cordura note book and pad.
It zips completely and fits well in my left BDU hip pocket. I drew a particular terrain feature on the water proof paper last weekend during a 5 mile ruck while sweating like a pig and had no problems with my sketch.

Found this item at General Jackson's on Yadkin Ave just off Ft. Bragg. I have no doubt that I was overcharged but I like Rite in the Rain stuff better than anything I found at Clothing Sales on Ft Bragg, Ft Jackson, or Charleston AFB.

The MCSS at those posts didn't stock Rite-In-The-Rain notebooks?

Razor: They had the Right in the Rain 4x6 note pads but only Gen Jacksons had the HSLD coyote/desert tan cover with pen slots and a pocket-all of which is closed with a zipper.

Might want to get in the habit of putting in one of your top pockets (under US ARMY or Name Tag). I remember plenty of times when crossing water obstacles or draws, when it looked shallow and I'd find myself sinking in waist deep. Even though it's waterproof...it's good to keep it dry as much as you can.

My $.02.