12 gauge. Ventilated rib. Beautifully engraved with a pheasant on one side and a wood cock on the other inlaid in gold. Wood is in excellent condition with most original lacquer. 1-5/8 inch DAC and 1-1/2 inch DAH. 15-1/2 inches LOP. Original Ithaca recoil pad. Overall gun is superb with 99% bright blue and nearly all vivid case colors. Beautiful gun inside and out.