... surface treaded The Largest Professional Roller shutter door manufacturer ! Shinilion Roller shutter door Introduction Aluminium roller shutterMaterial is ... be off. Pure manual only for roller shutter windowManual crank, Length: 0.6m, 0.8m,1.2mSurface treaded:powder-coating ... -proof , warm-keeping .Save energy design,when the roller shutter closed, can saving 30% energy, obstructed 100% sunshine. ...