I work at a race car chassis fab shop and almost every day I find myself making templates for paneling and tin work.These make it super easy to get a good clean and tight cut on the tin work. It makes fitting panels around roll cages trivial.I'll be using these almost daily for work, they increase my productivity by speeding my workflow up.They do exactly what you would expect them to do, the blue one has a lock that holds the "fingers" in place and both the blue and red one have magnets to help keep them in place.I forgot to take some pictures today at the shop with the tool, when I get back from vacation I'll take and post some pictures of it in use. It's a very handy tool.