It's also called aluminum walkboard. The plank hooks on the round pipes and then to be locked. Widely used for wall building and other constrction working. The main structure of the plank is made of aluminum alloy 6061 T6 while the main board is plywood. It's portable so easy to be moved and with strong structure. The plank is durable, can be used at any circumstance and the mail board can be replaced. The length can be very different per cutomers' requirement.