Adams Rite 4550R-01-121

The Adams Rite 4550R-01-121 is a right-handed MS Deadlock Lever with a dark bronze powder-coated finish matching 313 anodized hardware, designed for compatible Adams Rite MS Series deadlocks and cylinder-operated flushbolts. Its 3-inch spring-loaded lever unlocks the deadbolt with approximately 3 pounds of downward force and relocks it through a 90-degree upward rotation. Featuring a mechanical LOCKED/OPEN status indicator and clutch-protected operation, the 4550R-01-121 accommodates 1-3/4-inch to 2-inch-thick doors and supports right-hand or right-hand reverse installations.

Adams Rite 4550R-01-121 MS Deadlock Lever with Indicator, Right Hand, Dark Bronze

The Adams Rite 4550R-01-121 MS Deadlock Lever provides convenient interior operation for compatible Adams Rite MS Series mortise deadlocks and cylinder-operated flushbolts. Manufactured by Adams Rite, an ASSA ABLOY brand, this mechanical lever trim features a right-hand configuration, 121 dark bronze powder-coated finish matching 313 anodized hardware, and integrated mechanical lock status indicator. Designed for narrow-stile aluminum storefront doors and compatible commercial metal door assemblies, the lever installs in place of an existing interior key cylinder or cylinder-type thumbturn. Its spring-loaded construction simplifies manual deadbolt operation while preserving the existing exterior key cylinder function, making it suitable for commercial storefronts, offices, institutional buildings, and controlled-access entrances.

The 4550R-01-121 features a 3-inch (76.2 mm) aluminum lever with an end-return design that retracts a compatible MS deadbolt with approximately 3 pounds (1.36 kg) of downward force. Rotating the lever downward 90 degrees unlocks the door, while releasing it returns the handle to its horizontal resting position. A separate 90-degree upward rotation extends the deadbolt to relock the door. The integrated mechanical indicator displays LOCKED in red lettering or OPEN in green lettering against a white background, reflecting the actual bolt position. An internal clutch mechanism helps protect the lock components against excessive operating force. The cast aluminum housing measures approximately 1-3/8 inches wide, 7-1/2 inches long, and 1 inch deep, providing a narrow-profile control for commercial door hardware installations.

The Adams Rite 4550R-01-121 is factory-configured for right-hand (RH) or right-hand reverse (RHR) doors and accommodates door thicknesses from 1-3/4 inches to 2 inches (44.5-50.8 mm). Its handing can be reconfigured in the field when required. Compatible locking hardware includes the MS1850S, MS1850SN, and MS1950 Series deadlocks, along with 1870 and 1870HM Series cylinder-operated flushbolts. The lever also supports selected single-point and threshold bolt-equipped locking systems using the supplied drive components. It is not compatible with 7/8-inch (22.2 mm) backset locks, MS+1890 deadlock/deadlatches, or 2190 interconnected deadlock/deadlatches. The 4550R-01-121 is supplied as interior lever trim rather than a complete deadlock assembly, requiring a compatible existing or separately purchased lock body.

Installation of the Adams Rite 4550R-01-121 uses the interior cylinder or thumbturn opening of a compatible MS deadlock, with additional door stile preparation for the mounting screws and mechanical indicator. The standard package includes mounting hardware and drive pins for single-point and threshold bolt-equipped locks. The lever housing projects approximately 11/16 inch (17.5 mm) forward of the cylinder backset centerline, making door stop clearance an important installation consideration. Its fully mechanical operation requires no batteries, electrical wiring, or programming. The spring-loaded lever and approximately 3-pound operating force support accessible hardware applications, although final ADA accessibility, ANSI/BHMA compliance, and emergency egress suitability depend on the complete door assembly and applicable building codes. The 4550R-01-121 provides a durable mechanical trim solution for maintaining or upgrading compatible Adams Rite MS deadlock installations.