The FuMO 24 and 25 (Funkmess-Ortung (Radio-direction finder, active ranging)) were designed as a replacement for the earlier FuMOsearch radar for Nazi Germany's Kriegsmarine in 1943. The differences between the two models are not clear and it usually used a larger 2-by-6-meter (6 ft 7 in × 19 ft 8 in) antenna than the older system.[1]