A modern Russian 56 hour marine chronometer
XPOHOMETP MOPCKON TV 25-07 1533-84The 4in. dial with Arabic numerals, single chain driven movement, the double case with brass gimbal and carrying handles, serial no. 18838 (with winder) 19cm wide, 19cm deep, 19.5cm high, (7in wide, 7in deep, 7 1/2in high)