Desk-Top Drafting Board: A3 - Compact & Lightweight Ideal for Learners sturdy board made of indestructible, non-warping material Ergonomic design for comfortable, effortless operation For sheets up to 450 by 325 mm in size Scale-equipped magnetic clamp Four sides of straight edge guide slots with signal bumps Additional metal clamp Parallel straightedge with grip area and STOP-and-GO button