Options to use as an extension ladder, single ladder, double ladder or extendable double ladder – all possi ble thanks to special joints. Safe free standing of ladder thanks to cross-piece. Aluminium stiffener with pushbutton locking. Manual length adjustment rung by rung using engaging hook. Secured against lifting out and sliding out of position. Easy handling in all variants. Optionally rollers with rubber tyres to protect the wall surface when extending/retracting ladder are available.