This is a Duo-Fast pocket stapler. It's about as big as a medium-sized pen, and when you close up the stapler, you put the cap over it, and it sits in your pocket just like a pen. It appears they were made from the 1950s to the 1970s. This one's new in the box, with instructions and staples.
Now, you have to understand that I just had to buy it, and because if I hadn't, I might have sent the entire universe tumbling out of whack. There was just too much going on that day to leave it at the yard sale where I spotted it.
You see, I was checking Facebook one morning, and noticed a post from pen dealer Richard Binder. It seems a friend made him a gift of one, and he started his post by saying, "I'll bet none of you have one of these." About two hours later, a friend called and said she was at a yard sale, and there was a table filled with pens. So I went. And the first thing I spotted was this.
Now, two hours prior, I had no idea such a thing existed, and here I was looking at the second one to cross my path--one virtual, one in front of me. Had I left it there, I'm sure a wormhole would have opened in the sky above me and taken me off to some weird hell where books are all electronic, and you can only write with your thumbs. So I bought it. I know better than to tempt fate.