Our 10" Aviator Style Wall Clocks are made to closely portray primary cockpit flight instruments. Each clock features the actual shape of an aircraft instrument and a replicated dial. Measurements are 10" Square x 1 3/4" Depth. These clock movements require a quality brand name or high alkaline battery. Always check to ensure battery is placed in the cradle correctly (+ to + and - to -) and then give it a slight 'roll' to ensure contact is made.