Since 2014 we have worked extremely hard to find, invent and improve high quality security products for you, our buyer! We started with the idea that professional service providers, homeowners and DIYers should all have access to top-quality high-grade hardware, without the middleman. Over the years, we searched and found the best factories, materials, assemblers, and installers to offer you the best quality lock, key, and hardware products. We source only the best quality materials and ensure top level quality control in our factories. Our unique DTC (Direct to Consumer) model allows us to offer professional grade products to retail buyers at wholesale prices. We stand behind our quality products! All Ri-Key Security products purchased come with our promise, if you are not happy with the product or have any issue with your purchase, please contact the seller immediately and we promise your issue will be resolved. Standard , standard 1-5/32" diameter lock mortise cylinders fit Adams Rite, Kawneer, Vistawall, & Most other Locksets Standard 1-inch Length - the most common size cylinder for commercial glass/aluminum storefront doors. However, there are other common sizes such as 1-1/8" or 1-1/4". Please confirm your lock size to avoid mismatch! The lock cylinders have Adams Rite cam for use with Adams Rite, Kawneer, Vistawall, & most other storefront door locksets. If your lock uses a different cam type, this may not fit your setup. For use with commercial store front, glass doors with narrow aluminum frame with deadbolt, hook lock, or deadlatch. Also fit many residential doors with mortise lock set, please confirm lock size and cam to ensure your lock accept this type of cylinder. 2 Keyed lock cylinders & 4 matching keys, and 2 trim ring Unscrew face-plate screws and loosen the Set screws (flat-head/hex small ones, located behind the face-plate) Unscrew the old mortise cylinder off your lock, by turning it . If you have an Anti-Wrench Mortise Cylinder Guard around it, you can use an old key as a tool, insert it into the key hole and use it to help you get the initial turn to loosen the cylinder ( not to break it inside the cylinder). If you find it difficult to turn, you can try to loosen the 2 mounting screws that hold the lock on the door. Don't remove them! Just loosen them to allow the mortise lock and cylinder to be more free inside the door frame. Start by turning the cylinder until you feel your new cylinder and mortise lock threads are aligned. Turn your new cylinder until it is deep enough to engage the mortise lock pivot pin. * not to the cylinder as this may ruin the entire lock! * the cylinder. If the cam touches the metal lock rod behind it, it will prevent it from turning smoothly. * If you find it difficult to screw in, you can try to loosen the 2 mounting screws that hold the lock on the door. Don't remove them! Just loosen them to allow the mortise lock and cylinder to be more free inside the door frame. Align the cylinder so that the keyway is in the same position as it originally was (usually to the bottom, parallel to the door frame). * Your new mortise cylinder has 2 grooves on both sides. The set screws be aligned with one of those grooves to secure the cylinder in place! Tighten the set screw until your new cylinder cannot move in place. Screw back the face-plate.