Imirongo imwe ya silindrike ya roller ifite akazu kagizwe na silindrike yazengurutswe hagati yimpeta ikomeye ninyuma.Ibi byuma bifite urwego rwo hejuru rwo gukomera, rushobora gushyigikira imizigo iremereye kandi ikwiranye n'umuvuduko mwinshi.
Impeta y'inyuma ya NJ ya silindrike ifite imbavu ebyiri zihamye, mugihe impeta y'imbere ya silindrike ifite imbavu imwe ihamye.Ibi bivuze ko ibyuma bya silindrike ya NJ ishoboye gutondekanya igiti mu cyerekezo kimwe.
