The Design Hardware mortise cylinder is cut to the C keyway, 6 pin, so it runs on the same keyway family as a Schlage C system. It ships keyed different, meaning each cylinder comes on its own key change rather than matched to your existing keys, so a locksmith would need to re-pin it to your bitting to bring it onto an existing master system. If you want a factory C-keyway core instead, the Schlage 20-057-C is a full size interchangeable core cylinder in C keyway.

As supplied, no. The Design Hardware mortise cylinder is keyed different, so each one arrives on its own unique key change. Forty of them means forty separate keys. For a property on one key, either have a locksmith re-pin them all to a common bitting, or move to an interchangeable core platform where you control the pinning yourself, such as the BEST 1C 5-pin core or the 1CB 150 Series interchangeable core, both of which pull and swap without taking the lock apart.

No, and they are not interchangeable. A mortise cylinder like the Design Hardware 1-1/8 inch 6 pin C keyway threads into the lock case and turns a cam. A rim cylinder mounts through the door and drives a tailpiece into a rim device: the Schlage 20-021 is a 6-pin rim cylinder with a vertical tailpiece cam, the Schlage 20-022 is the same cylinder with a horizontal tailpiece cam, and the Corbin Russwin 3070 is a 6-pin rim cylinder housing with a 1-7/8 inch tailpiece. If the exit device or auxiliary lock on the door takes a rim cylinder, a mortise cylinder will not mount to it.

Step up to a longer mortise housing. The Corbin Russwin 1070 is a 1-1/4 inch 6-pin mortise housing with an A01 cloverleaf cam, and the Corbin Russwin 1000 is a 1-1/2 inch mortise cylinder with an A02 straight cam. Both are Grade 1 series mortise cylinders. Confirm the cam style the lock body requires before ordering, since the cloverleaf and straight cams are not interchangeable.

An interchangeable core system lets maintenance staff swap the core with a control key rather than removing and repinning the cylinder. The BEST 1CB is a 150 series interchangeable core cylinder, the BEST 1C is a standard 5-pin cylinder core, and the BEST 1CDF is a drill resistant patented interchangeable core 7-pin brass 150 series core. On the Schlage side, the 20-057 is a 6-pin FSIC rim cylinder with a convertible tailpiece cam and the 20-057-C is a full size interchangeable core with a C keyway in 643E aged bronze. The Design Hardware 1-1/8 inch cylinder is a conventional keyed different mortise cylinder, so choosing between them is a decision about whether the facility standardizes on core swapping.

The Corbin Russwin 1080 is a Grade 1 series 1-1/2 inch LFIC mortise cylinder, 6-pin, built for Schlage L9000 mortise locks with an A01 Schlage L cam. It is a small format interchangeable core housing, so the core can be pulled with a control key. The Design Hardware 1-1/8 inch mortise cylinder is a conventional 6 pin cylinder in the Schlage C keyway. The deciding factors are the cylinder length the lock case needs, the cam the L9000 requires, and whether the site keys conventionally or on interchangeable cores.

Six finishes, and they cover the common trim families: US3 bright brass, US4 satin brass, US10B dark bronze, US26 bright chrome, US26D satin chrome, and US32D satin stainless. For a building already standardized on satin chrome lever trim, US26D is the match; dark bronze storefronts take US10B. Cylinder finish only needs to match the collar and the lock face the buyer sees, not the internal lock.

Cylinder only. The Design Hardware 1-1/8 inch mortise cylinder is a replacement part that threads into a mortise lock case you already have installed, so it swaps the keyed portion without touching the lock body, the trim, or the door prep. If the lock itself is worn or the function is wrong, replacing the cylinder will not fix it.

The Detex MC65 is the closest match on paper, a 1-1/8 inch 6-pin mortise cylinder in Schlage C keyway. Where the two differ is brand alignment on the rest of the opening: if the door already carries Detex hardware, the MC65 keeps everything under one manufacturer. If you need a 6-pin mortise housing in a longer body, look at the Corbin Russwin 1070 at 1-1/4 inch.

Key-in-knob and key-in-lever locks take a cylinder built for that lock chassis, not a threaded mortise cylinder. The Kaba Ilco 1539 is a key-in-knob and lever universal cylinder, the 1599 is a key-in-knob replacement cylinder, the 1579 is a knob and lever cylinder for Sargent, and the 1549 is a key-in-deadbolt cylinder. Falcon offers the A23161-05 G key-in-lever cylinder in a 6-pin G keyway, keyed different, with two cut keys. Identify the lock chassis first, because none of these drop into a mortise lock body.

A cylinder pull combines the cylinder with a grip so the door can be pulled open, which a bare mortise cylinder does not provide. The Adams Rite 4024 is a cylinder pull with trim plate mounting for MS1847 deadlock systems, and the 4025 is a five pin tumbler cylinder pull with through-screws for the MS1847 deadlock. For a wood door application, the 4026 is a five pin tumbler cylinder pull designed for the Adams Rite 5017 wood door deadlock. Choose the pull when the opening needs a pulling surface as well as key control.

Those openings take rim type lazy motion cylinders sized to the lock they replace. The Medeco 1012040 is a 6-pin lazy motion rim cylinder for Kwikset single cylinder deadbolts, the 1075127 is a 5-pin rim type lazy motion single cylinder for handlesets and deadbolts, the 1065244 is a 5-pin rim lazy motion cylinder with an Emtek tailpiece, and the 1065140 is a 5-pin retrofit cylinder for the Arrow JL interconnected lock and Emtek handleset and deadbolt outside cylinder. Emtek also lists the CY4 cylinder as a replacement part. The Design Hardware 1-1/8 inch mortise cylinder threads into a mortise lock case and does not fit these.

A dummy cylinder fills the prep and matches the appearance without operating anything. The BEST 12E series dummy rim cylinder has a 1-5/32 inch diameter for that purpose. The Design Hardware 1-1/8 inch mortise cylinder is a keyed different working cylinder, so ordering it for a blank opening means paying for key function you will not use.

Six pins give more possible key changes than five, which matters when you are keying a large system and need enough unique changes without duplicates showing up across the property. It is not pick resistance in itself. If drill resistance and patented key control are the actual concern, that is a different class of product, like the BEST 1CDF drill resistant patented interchangeable core, which is also a 7-pin brass core.