I bought this tool many years ago because I thought it was interesting, and I didn't really know what it was made to do.
It is adjustable lengthwise and the two ends are adjustable for angle. 30" closed up and 49 1/2 " opened up. I used it once to make shelves to fit a big cupboard that wasn't square. I paid $30 for it and want to get my $30 back out of it. CASH ONLY PLEASE. If it's still listed it's still available. Thanks for looking.