Adams Rite 4550 MS Deadlock lever Trim

The Adams Rite 4550 is the MS Deadlock lever trim for the inside of commercial aluminum storefront doors. It replaces the existing key cylinder or thumbturn-style cylinder with a spring-loaded egress lever and a built-in lock-status indicator, converting any compatible Adams Rite MS deadlock into a single-motion exit device. About 3 pounds of downward force on the 3-inch lever retracts the deadlock for exit; the lever returns to horizontal under spring tension. Pushing the lever upward 90 degrees throws the deadlock again. The indicator window shows "LOCKED" in red letters or "OPEN" in black letters on a white background, driven directly by the lock bolt itself rather than a secondary mechanism, so the displayed status always matches the actual deadlock state. Outside key operation stays unaffected. Internal clutching action protects the trim from damage if the lever is forced when the bolt is bound. Field-reversible for left-hand or right-hand swings without ordering different parts. SKU 4550.

About Adams Rite and the 4550 Function

Adams Rite, founded in 1958 and part of ASSA ABLOY since 1989, is the dominant brand for narrow-stile aluminum storefront door hardware in North America. The MS Series of pivoted-bolt deadlocks (MS1850S, MS1950, MS1837 and similar) is Adams Rite's flagship lock platform for retail storefronts, restaurants, professional offices, and any commercial entry using narrow-stile aluminum doors. The 4550 lever trim solves a specific problem on those installations: customers, employees, or after-hours staff inside the building need to exit quickly without fumbling for a key, but the deadlock itself is bolted, not latched. With the 4550, exit is one downward push on the lever, similar to a panic device but without the cost or door-prep complexity of full panic hardware.

Specifications

Housing: aluminum casting, 1-3/8" W by 7-1/2" L by 1" D. Lever: 3" aluminum with end-return design. Operation: turn lever downward 90 degrees to unlock; lever returns to horizontal under spring load; turn upward 90 degrees to relock. Unlock force: approximately 3 pounds. Indicator: "LOCKED" red or "OPEN" black on white background, driven by the lock bolt. Stop clearance: housing projects 11/16" forward of cylinder backset centerline. Door thickness: 01 for 1-3/4" to 2" doors; 02 for 2-1/8" to 2-3/8" doors. Finishes: 119 Black Anodized (matches Adams Rite 335), 121 Dark Bronze Anodized (matches 313), 130 Clear Anodized (matches 628). Handing: LH or RH, field-reversible. Standard package: trim assembly, installation instructions, mounting screws, drive pins for single-point and threshold-bolt-equipped locks.

Compatibility (Which Adams Rite Deadlocks Work with the 4550)

The 4550 fits any Adams Rite MS pivoted-bolt deadlock, including Schoolhouse versions. Confirmed compatible models: MS1850S, MS1950, MS1837, plus derivative units that bolt into the threshold including the 1870, 1870HM, and 1877 flushbolts. The 4550 is NOT compatible with the MS+1890 Deadlock/Latch combination or with any 7/8" backset locks. Verify the deadlock model number stamped on the existing faceplate before ordering.