Seco-Larm SD-C121-S1 Door Closer Size 2

Fixed Size 2 Surface Door Closer for Lighter Commercial Doors

The Seco-Larm SD-C121-S1 is a surface-mounted door closer for metal or wood doors weighing up to 100 pounds and measuring up to 42 inches wide. Its fixed Size 2 spring force is suited to lighter doors that do not require the higher closing force or broader adjustment range of a heavier commercial closer.

Separate sweep and latch valves allow the closing cycle to be adjusted in two stages. The sweep valve controls the main movement of the door, while the latch valve regulates the final 15 degrees of travel to help the door close against the frame and engage the latch without excessive impact.

The SD-C121-S1 has a reversible, non-handed design for use on left- or right-hand doors. It supports regular-arm and top-jamb installation and includes the required mounting hardware. Its cast-aluminum body, forged-steel arm, and silver finish make it suitable for offices, interior access-controlled doors, utility rooms, multifamily properties, and other openings within its rated size and weight limits.

Key Features

• Fixed Size 2 surface-mounted door closer
• Designed for metal or wood doors
• Supports doors up to 42 in. wide
• Rated for door weights up to 100 lb.
• Independent sweep-speed and latch-speed adjustments
• Latch-speed control covers the final 15° of closing travel
• Reversible, non-handed design
• Suitable for left- or right-hand doors
• Supports regular-arm and top-jamb installation
• Cast-aluminum closer body
• Forged-steel arm assembly
• Silver finish
• Maximum hinge-side opening angle of 120°
• Installation hardware included
• One-year manufacturer warranty

Technical Specifications

• Manufacturer: SECO-LARM
• Brand: ENFORCER
• Model / Part Number: SD-C121-S1
• Product Type: Surface-mounted hydraulic door closer
• Closing Force: Fixed Size 2
• Closing-Force Adjustment: Not adjustable
• Sweep Speed: Adjustable
• Latch Speed: Adjustable
• Latch Range: Approximately 15° to 0°
• Back Check: Not listed
• Adjustment Valves: One sweep valve and one latch valve
• Handing: Reversible, non-handed design
• Maximum Door Width: 42 in. (1,070 mm)
• Maximum Door Weight: 100 lb. (45 kg)
• Compatible Door Materials: Metal or wood
• Maximum Hinge-Side Opening: 120°
• Installation Configurations: Regular arm or top jamb
• Parallel-Arm Installation: Not listed
• Body Construction: Cast aluminum
• Arm Construction: Forged steel
• Finish: Silver
• Mounting Footprint: Approximately 5-3/16 x 3/4 in. (132.8 x 19 mm)
• Closer Body Length: Approximately 5-1/2 in. (140 mm)
• Closer Body Height: Approximately 2-5/16 in. (58 mm)
• Product Weight: Approximately 2.25 lb. (1.02 kg)
• Included Components: Door closer, forged-steel arm assembly, and installation hardware
• Warranty: One year
• Installation Note: Sweep and latch speeds should be adjusted for the door, frame, latch hardware, and site conditions

Conclusion

The Seco-Larm SD-C121-S1 provides controlled automatic closing for metal or wood doors within its 42-inch and 100-pound limits. Its fixed Size 2 force, independent sweep and latch adjustments, and non-handed design make it suitable for lighter commercial and controlled-access doors using regular-arm or top-jamb mounting.