Also called free lift. Lift is experienced by the fork of a forklift stacker before it projects through the upper end of the mast assembly inner mast. There are differences between what is known as standard free lift (usually 280mm.) In double acting telescopic masts. The special free lift can be calculated in the free-lift truck by the formula: Height 650mm less. equal to free special lift. The exact details of each machine characteristics are provided by individual datasheets published by the manufacturer of the truck. The special free lift is generally necessary to stow inside closed areas with relatively low ceilings.