Professional triangular metric drafting scales by Alvin and Fairgate. Select from metric drawing scales constructed of durable hardwood, aluminum, plastic, or bamboo. Available in different colors, lengths, and graduations from 1:2.5 mm up to 1:2500mm. Choose the metric scale that best fits your specific job, style, and budget. Triangular metric draftsman scales are the perfect tool for drafting, drawing, floor plans, sketching. Great for engineers, architects, mechanical draftsmen.