These are the most modern types , totally aluminium structure with steel roll tube,ball-bearing and the slats are anodized(eloxated) aluminium profile,filled with polyurethane foam for sound- and thermal insulation.Slats have plugs to avoid any possible sideway movement of the profiles-Side Lock System- and they reduce noise and let the roller shutter last longer.They have aluminium guide rail with a brush inside and overwinding is blocked by a hidden backstop.Roller shutters can be moved manually by tape,cord or by tubular motors to provide maximum comfort for you.