SL18 – CONCEALED CONTINUOUS GEAR HINGE Suitable for aluminum doors weighing up to 300 lbs. Recommended for heavier doors and/or very high traffic entrances. Eliminates the gap between the door and the frame, providing a weatherproof, tamper-proof barrier. When the door is closed, there are no accessible screws, bolts or pins. Requires clearance at hinge side between door and frame. Used on #175, #350 & #500 series doors. SL11 – CONCEALED CONTINUOUS GEAR HINGE FLUSH MOUNTED Suitable for aluminum doors weighing up to 300 lbs. Recommended for heavier doors and/or very high traffic entrances. Eliminates the gap between the door and the frame, providing a weather proof, tamper-proof barrier When the door is closed, there are no accessible screws, bolts or pins. Requires clearance at hinge side between door and frame. Used on #275, #200T & #500T series doors. 179 – BUTT HINGE Suitable for aluminum doors weighing up to 150 lbs. Roller bearing, non-removable pin. Zinc, bronze painted or stainless steel available. SL21 – FULL SURFACE CONTINUOUS GEAR HINGE Suitable for aluminum doors weighing up to 300 lbs. Recommended for heavier doors and/or very high traffic entrances. Surface mount on face of existing or new door and frame. Ideal for renovation. (retrofit) Swing clear action. Tamper-resistant, removable door leaf cover. SL57 – FULL SURFACE CONTINUOUS GEAR HINGE Suitable for aluminum doors weighing up to 300 lbs. Recommended for heavier doors and/or very high traffic entrances. Surface mount on face of existing or new door and frame. Ideal for renovation. (retrofit) Tamper-resistant, removable door leaf cover. SL53 – HALF SURFACE CONTINUOUS GEAR HINGE Suitable for aluminum doors weighing up to 300 lbs. Recommended for heavier doors and/or very high traffic entrances. Mounts on door face and frame rabbet. Ideal for renovation. (retrofit) Tamper-resistant, removable door leaf cover.