Hamilton Watch Co., Lancaster, Penn., model 21 chronometer no. 4810, key wound, two day, fourteen jewel movement with cotes de Geneve decoration, fusee, spring detent escapement and helical hairspring, matte silver Arabic numeral dial with up/ down

Hamilton Watch Co., Lancaster, Penn., model 21 chronometer no. 4810, key wound, two day, fourteen jewel movement with cotes de Geneve decoration, fusee, spring detent escapement and helical hairspring, matte silver Arabic numeral dial with up/ down indicator, dial signed Hamilton Lancaster Pa., U.S.A., black finished steel hands, original winding key, brass bound mahogany box with gimbals and locking lever, inside of box lid with instructions and illustration of correct way to lock balance, includes Hamilton marine chronometer display card, c1941 Running well, minor scuffs and scratches on movement, dial and hands very good, glass with scratches, box with scratches on top and minor wear, instruction sheet inside lid very good, but does not reference the locking device used in this chronometer, display card also very good Ht 7 1/2", L and W 7 5/8"