This is a solid brass polished porthole wall clock with both 12 and 24 hour, (ships time), and measures 5½" in diameter. This nautical wall clock features a quartz movement and thick glass incorporating a 3/16" polished bevel around the outer edge. Three screw are required to secure this beautiful item in the location of your choice and the battery is accessed by undoing the dogs and opening the glass face. This nautical clock makes the perfect addition to your nautical home decor. It could help turn that special area in your nautical home or office into your own beach house, coastal themed area. They also make a great nautical gifts, a beautiful piece of coastal decor, a nice piece of nautical wall art as well as being a great addition to your nautical decoration.