Arteza 12" Triangular Architect Scale Aluminum Color-Coded Grooves (Imperial) One 12" Triangular Architect's ruler features 3 sides with 6 different scales Professional grade for supreme accuracy Color-coded grooves for quick and accurate selection of the desired scale Made from high grade anodized aluminum Imperial Scale: 1-1/2", 1, 3/4", 3/8", 3/16", 3/32", 1/2" 1/4", 1/8", 3, 16