This insulator is a CD 303 top and a CD 310 base known as a Muncie. It is embossed on the front; "HEMINGRAY PATENT MAY 2ND 1893" and "MUNCIE TYPE on the back. It is an aqua color. The really cool thing about this Muncie is it has a 3/4" "Cyclops Bubble" on the top part of the base. The top and the base are in very near mint + condition with almost no signs of wear. A very nice displaying piece. Priced at $275.00 plus shipping.