Typically, different cylinder types and formats are not consistent between manufacturers. Each cylinder manufacturer designs and develops their own key system specifications. Cylinder and key system specifications are not standard. This means that if you have a variety of hardware, each of the cylinders that lock those hardware pieces, and the internal key system components, are different from one another. The cylinders and their keys are not compatible with one another, which mean you are carrying multiple keys, stocking multiple cylinder pieces and components, and have different key system records to manage. There are some key systems on the market today that are completely retrofitable to existing hardware components and allow all locks and cylinders to be tied together under a "uniform" (one key) key system. Different types of cylinder formats would include: Rim cylinder Mortise cylinder Key-in-knob cylinder Key-in-lever cylinder Small Format Interchangeable Core (SFIC) Large Format Interchangeable Core (LFIC) Cam Locks (3/4" diameter) Language to use in key system specification:The manufacturer shall provide a system where many cylinder/core formats can be operated by a single key within the same key system (Cylinder/core formats couldinclude, but not be limited to: rim/mortise/KIK/KIL/SFIC/LFIC/Cam Locks).