M Pro Series - Wheelbase Supportbar 750mm - Part for Pro Series, supportbar for Wheelbase, steel , stand for rail mounting - wheel-standing - black. M Pro Series - Wheelbase Supportbar 750mm - is mainly made out of a light weight metal construction that is both heavy duty and will support most ideas and environments it is placed in. M Pro Series - Wheelbase Supportbar 7500mm - Black is made to fix inbetween M Pro Series - Wheelbase 180/270/300cm Pro. This part should be combined with other items.