These Thunder Mugs measure 4" in Diameter at the base, Stand 7" tall and have a bore of 1-25/32"(golf ball) X 5-1/2" deep.1/8' vent/fuse hole. Forged handle with decorative twist. Weighs 14lbs
 
Historical info: Signal cannons were used by ships coming into harbor, which would signal the authorities in port to come and inspect the ship before it offloaded any goods or crew. Thunder mugs were especially useful during the time of the Black Plague, when incoming ships had to be screened for the disease before crew could go ashore.