A collapsible spider wheel assembly on a towing device enables storage of
the device into a standard rectangular space. Once collapsed, the
collapsible spider assembly is protected within the body of the towing
device. Furthermore, actuation of the folding and unfolding may be
accomplished through the usual telescoping of the carrying handle of such
a device, such as in a suitcase embodiment. While the spider wheels are
in the open position, the carrying apparatus may exert a drive force to
climb up stairs and braking force to descend stairs. The unit operates as
a normal wheeled carrying apparatus while traversing a horizontal
surface.