; Slats: Can be made of
plastic, wood, or metal, such as extruded or roll formed steel,
aluminium or stainless steel. Single or multi wall. Hollow or insulated designs. Shutters used to protect against theft or adverse weather events are usually made of metal. ; Roller (or axle tube): Steel, aluminium tube supported at either end by an end plate. ; Shutter box: Formed steel or aluminium extrusion box designed to protect shutter's internal components. ;Shutter spring • Spring wire. Made from the spring wire, it also called torsion spring. • Flat spring. Formed by hardened and tempered steel strips in coils. Common steel grades C67, CK67, SAE1070, etc. • Not used in all types of shutters. ;Guide rail (or track):Steel or aluminium to retain the shutter curtain within the opening. Weather sealed to increase product lifetime and reduce operating vibration. ;Bottom slat: Steel, aluminium or
PVC to match the rest of the roller shutter curtain. Safety edge or rubber weather seal to reduce draught can be added. ; Lock: Important part of roller shutter used to manually secure the curtain slats in place. Can be locked with slide lock and bullet lock. Slim key locks are installed within the end slat and have bars that securely lock shutter into the guide rails. == See also ==