You’ve seen 12″ or maybe even 24″ combination squares, but how about a 48″ long combo square? Manny’s Woodworkers Place sells this jumbo four-foot version of the combination square in their online store.
The bar is machined from aircraft-grade aluminum and can also be used as a straightedge. Both English and metric markings run the length of the bar. It comes with two cast-aluminum heads: a center-finder, and a combination 45° and 90° head with an integrated spirit level.
If you have any use for such a large combination square you can get one for $33, plus $10 shipping.
48″ Combination Square [Manny’s Woodworkers Place]