Good one, beeliner.

Nice try, Donuel, but the tab is not sewn on the bottom. The small bag would drop right out.

But wait, I think Freddy Headey has nailed it. It's a rod holder.

http://www.rjroberts.com/Columbia-Long-Sleeve-Fishing-Shirt_p_228.html

Who'd a thunk it? The shirts seem so work-a-day, perfect for shop or truck. (I'm afraid to ask what a zinger is.)
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The shirts are for me. I find that men's clothes are better made and last longer than women's. I also like pockets for travelling. (Put your driver's license and boarding pass in the pocket, press down the Velcro, get in the security line knowing where everything is.)

Of course I am replacing the ugly, speckled male buttons, and I will add a pretty necklace to soften the effect. Still, some of the colors are pretty drab. But good for bird-watching, I guess.

I'm going to the Texas Toot, a great week of early music. Maybe I can use the funny little tab to hold a recorder swab.