Easy Peasy lines and angles with this well made measurement tool

I just played around with this tool a little to get a gist of it's limits.  It's well made, the 4 rulers can be used screwed together, and comes completely apart to store in a small space.  It works for literal contstruction measuring and, in conjunction with a triangle makes angles easy.  For architectual drawing, the unit has limitations with respect to size.  But, if used with other measuring tools, you can really have a lot of fun.  Reminds me of Spirograph when I was a kid.  Good gift for the avid angle loving architect/draftsman, artist!