It's the outside half of the trim on a Schlage L Series mortise lock: a full face cylinder escutcheon plate with the lever attached. It replaces the exterior escutcheon and lever on an existing L Series mortise opening, not the lock body or the latch. If the mortise case itself is the problem, this part won't fix it.

Yes, the 09-553 assembly is built for the Schlage L Series mortise lock and is offered with either the L or N escutcheon shape. Pick the one that matches the escutcheon already on your door, since the two plates are not interchangeable in appearance.

The 09-553 is the full face cylinder escutcheon and lever assembly. It's trim hardware. Plan on supplying the mortise cylinder and keying separately so it can be keyed into your existing system.

Exterior. The 09-553 is the outside escutcheon with the cylinder face. If you're rebuilding both sides of the door, you'll need the matching inside escutcheon assembly in the same L or N style, same lever design, and same finish so the two halves match.

No. The 09-553 trim is specific to the Schlage L Series mortise lock and its escutcheon prep. It won't mount on a cylindrical lockset, and it won't adapt another manufacturer's mortise case. For Corbin Russwin 2000 Series classroom mortise bodies, the part ZenSupply carries is the ACSI 8500 Gemini operator, which is a different animal entirely.

No. The 09-553 is a complete exterior trim assembly for Schlage L Series mortise locks, combining the cylinder, the lever and the escutcheon plate into one unit. A GMS 6-pin small format IC core is the keyed core only, supplied un-combinated with keys, pins, springs and caps not included, so it has no lever, no escutcheon and no mounting. The GMS core also needs a housing to sit in before it can go in a door. Order the 09-553 when you need the full exterior trim; order a core when the trim is already on the door and only the keying element is being changed.

L and N are two different Schlage escutcheon plate profiles. The 09-553 cylinder assembly is built either way, so order the letter that matches the existing trim on the rest of your openings. Mixing L and N plates on the same set of doors leaves a visible mismatch even though the lock underneath is the same.

Four Schlage lever designs are offered on the 09-553 exterior assembly: 03, 06, 07, and 17. All four mount to the same escutcheon assembly, so the choice is about matching the lever profile already in the building rather than about function.

Seven BHMA finishes: 605 bright brass, 612 satin bronze, 613E dark oxidized satin bronze, 619 satin nickel, 625 bright chrome, 626 satin chrome, and 630 stainless steel. For a building standardized on Schlage mortise trim, 626 satin chrome and 630 stainless are the two most common commercial choices.

The escutcheon accepts a mortise cylinder at the full face opening, so the way to get interchangeable core is through the cylinder, not the trim. ZenSupply carries GMS small format IC cores in 6-pin and 7-pin, plus the GMS Best SFIC straight mortise housing in 7-pin with a Yale cam. Cores ship un-combinated, with keys, pins, springs and caps not included, so a locksmith pins them to your system.

They sit at different layers of the same door. The 09-553 is the exterior trim package for a Schlage L Series mortise lock and includes the lever and the escutcheon along with the cylinder. The GMS ICM7-ST is a Best-format straight mortise housing, 7-pin, with a Yale cam - it is the threaded shell that accepts a small format core in a mortise lock case, with no lever or plate of any kind. A housing plus core changes how the lock is keyed; the 09-553 changes the visible exterior trim.

Not necessarily. The 09-553 is the full exterior trim assembly for a Schlage L Series mortise lock, carrying the lever in 03, 06, 07 and 17 styles and an L or N escutcheon. If the trim is intact and the issue is simply that the cylinder sits proud or recessed, a spacer product such as the GMS KIT-PART04 collars kit addresses cylinder depth alone. Choose the 09-553 when the lever, escutcheon or cylinder assembly itself is being replaced.

No. Finish matching on the exterior of the door is handled by the trim, and the 09-553 exterior full face cylinder assembly is offered in 605 bright brass, 612 satin bronze, 613E dark oxidized satin bronze, 619 satin nickel, 625 bright chrome, 626 satin chrome and 630 stainless steel. A GMS small format IC core, 6-pin or 7-pin, is the internal keying component only and is supplied un-combinated without keys, pins, springs or caps, so it does not determine what the door looks like.

That's a cylinder collar and spacing issue, not an escutcheon issue. The GMS KIT-PART04 collars kit is the part that takes up the gap and lets the cylinder seat tight against the face. Order it alongside the 09-553 trim if the existing cylinder length leaves the plug proud or recessed.