PROFESSIONAL DRAFTING TRIANGLES - Made for architects and engineers. Pacific Arc's drafting triangles will provide accurate lines and precise angles. This is the perfect plastic triangle for quilters, drafters, architects, engineers, and students alike. HIGH-QUALITY CLEAR TRIANGLES - These triangles are made from .080 inch thick and pure acrylic. The plain and strong edge is designed for long lasting use. With so many uses, from a drafting square to a quilting template, these clear acrylic triangles are perfect for any project. ACCURATE 18 INCH LENGTH- The non-graduated triangle is an accurate 18 inches long. With 30, 60, and 90 degree corners, this triangle is one of the most versatile tools any profession should own. Always be able to make perfect angles for any project. MONEY-BACK GUARANTEE - If this drafting triangle is not what you're looking for, we offer a money-back guarantee, backed by Amazon. THE PERFECT GIFT - Gift these professional triangles to the architect or engineer in your life.