Why choose tungsten alloy counterweight for aircraft?

Compared with the traditional material, you could find lead is not so heavy, besides, it is toxic; steel is heavy but the capacity is too large, however, when using tungsten alloy material, you will find excellent properties which are quite different from other material: well hardness, good corrosion resistance, wonderful shock resistance, high temperature resistance and environmental friendly, especially, the properties of small volume but high density, make tungsten alloy material as the top one for counterweight for aircraft.