The ultimate in combination ladders, the 'Skymaster' is six ladders in one. From the one ladder you can make:
Triple extension ladder
Double extension ladder
Single section ladder
Three section free standing step ladder
Two section free standing step ladder
Stairwell step ladder
All trade models have square rungs with rung locks and a wide stabiliser bar for extra safety as well as fabric safety straps and a single sided safety locking bar with spring loaded pin location.