Sew Square 10™ includes the following reference lines
E - Metro Rings, Rings Revival, and Double Rings square-up lines for setting triangle seams.
Sew Square 10™ also squares-up blocks in the following patterns:
Chic & Jazzy Curve It Up Deco Tic Tac Deco Tumbler
Lattice Revival Metro Lattice Metro Medallion Metro Waves
Mod Pineapple Urban Birthday Urban Candy Urban Nine Patch
Urban Tiles Double Starburst 70 & Sunny Posh Snowball
Sew Square™ rulers can easily be marked with a permanent marker (ie: Sharpie) for other patterns and other square up points. Marks can easily be removed with a little nail polish remover.