PREMIUM QUALITY:Our triangle scale ruler made of solid aluminum,very solid not rust,perfect for office drawing work or school classroom study. TRIPLE SIDED DESIG:Triangular Architect's ruler features 3 sides with 6 different scales,very convenient and useful for professional. LASER ETCHED TECHNOLOGY:Architect ruler for laser etched,laser etched technology effectively prevents scale numbers and markings from wearing off or fading away, they will not wipe or scratch off ever. WIDELY APPLICATION:metal rulers are good for technical, artists, architects, engineers, teachers, and students
