H4 Button.

Vehicle: Some part-time Toyota Landcruisers.

• Part-time 4wd with a H4 button; this button selects H4.
• When going from the H2 position to H4,  just press the button do not move the lever (the lever is to select and deselect to and from L4).
• Makes shifting on the fly easy as long as free wheeling hubs are locked and the vehicle is in a straight line.

NOTE: Ensure free wheeling hubs are LOCKED before pushing the H4 button.  Especially on the fly otherwise you can damage your transfer box.