Vintage Find Friday

My friend Jeni scored the cutest knitting notion for me. It is a Raglan Sweater Wheel. You run across these wheels in games and children's books. You rotate a paper wheel behind or inside another paper wheel and line up words, pictures, or symbols and gives you an answer. I am sure there is a technical term for this device. If you know it, let me know. Well, in this case, it dials up a formula for a raglan sweater.