Together with the predecessor M250 and the revised sucessor model M260, the M251 was Menck's biggest “universal excavator”. What was called “universal excavator” by Menck were machines that could be equipped with different booms. For the M251 a front shovel was available as well as a lattice boom for grab and dragline operation. The Menck M251 was powered by a 12 cylinder diesel engine with 254 hp (189 kW) and had an operating weight of approximately 80&nbesp;tonnes (175,000 lb). It was built from 1955 to 1966.

The NZG shows the dragline version of the machine.