Solid brass antitheft lock core with AB key system designed to provide controlled access and reliable longterm performance. Key benefits Controlled access: A key is a decoration key intended for use by installers or decoration workers. B key is the master key. When the master B key is inserted, the A key is automatically disabled, providing secure master control. Improved security: The AB key arrangement allows property owners or managers to retain ultimate control while still permitting temporary access for authorized workers. Durable construction: Made from solid brass for corrosion resistance, strength, and long service life. Smooth operation: Precisionmachined components reduce wear and ensure consistent key action and locking performance. Features and specifications Product type: Antitheft lock core with AB key system. Keys: Two types, A and B. A serves as decoration key for temporary use. B serves as master key; insertion of B renders A inactive. Material: Solid brass lock core and key components for durability and reliable operation. Function: Provides controlled access and master override capability without changing external hardware. Practical applications Renovation projects: Allow decoration workers to access premises with the A key during work while retaining master control with the B key to secure the site when needed. Property management: Enable temporary access for contractors or cleaners while property managers keep master control to prevent unauthorized use. Office or shared spaces: Use for areas where controlled, timelimited access is required without replacing the entire locking mechanism. Usage notes Use this lock core as a replacement or upgrade when a controlled access AB key arrangement is needed. Ensure keys are stored and managed according to your access policies to maintain security. Soft notes Conversion: 1 cm = 10 mm = 0.39 inches. Color may vary slightly due to lighting and screen differences. Allow 0.5 to 2 cm difference due to manual measurement. This lock core provides a straightforward, mechanical method to separate temporary user access from master control while using a durable solid brass construction for dependable everyday use.