Make straighter cuts using your circular saw. Instantly aligns your saw to the cut line. Molded guides ensure your circular saw is perfectly square to the cut line. Reduces dangerous kickback, binding, and bent blades. Cut timber, siding, I-beams, trim, stairs, treads, and more. Turns your circular saw into a precision cutting tool. Perfect 90 deg. cross-cuts, every time. Helps prevent tear-out. 45 deg. to 90 deg. layout square. Prevents your saw from scratching your work. Use for marking, measuring, and layout. ABS polymer is tough and durable.