2-6 Tread Units: Mobile on 2 rear. wheels 150mm dia and 2 front spring loaded castors to achieve weight reactive function. Units move freely when pushed (unmounted) & stand firmly on the ground once they are mounted in use.
7-10 Tread Units: Made mobile on 150mm wheels & the use of a unique grip lift mechanism facilitating movement on 75mm retractable castors Available with Expanded Steel, Phenolic or Aluminium Treads.
