Schlage Residential F51A Bell Knob Entry Lock with C Keyway Single CylinderProfessional Residential Entry Lock SolutionThe Schlage Residential F51A Bell Knob Entry Lock delivers reliable keyed entry security for residential applications. This Grade 2 cylindrical lockset features a classic bell knob design with C keyway cylinder, dual backset compatibility for 2-3/8″ or 2-3/4″ installations, and fits door thicknesses from 1-3/8″ to 1-3/4″. Constructed with zinc and steel components and certified to ANSI/BHMA standards for dependable performance.Professional Features & BenefitsDoor Thickness Compatibility: Accommodates 1-3/8″ to 1-3/4″ doors with dual backset options for 2-3/8″ or 2-3/4″ installations.Keyed Entry Function: Single cylinder operation unlocks when door is opened from inside, with manual turnbutton locking from interior for convenient access control.Grade 2 Construction: ANSI/BHMA A156.2-2017 Commercial Grade 2 and A156.39-2015 Residential Grade AAA certified for reliable performance.Universal Installation: Dual backset latch fits either 2-3/8″ or 2-3/4″ backsets with easy 3-step installation requiring only a screwdriver.Complete Hardware Package: Includes 1″ x 2-1/4″ latch with 1/4″ radius corner faceplate, 1-5/8″ x 2-1/4″ radius corner strike, and two keys per lock.5-Pin Security: C keyway cylinder with 5-pin configuration keyed alike (KA4) for consistent key management.Fire Door Compatible: Available UL Listed for 3-hour fire door applications (F51A function) for enhanced safety compliance.Manufacturer Warranty: 10 Year warranty coverage for added confidence and protection.Standard FeaturesCertification: ANSI/BHMA A156.2-2017 Commercial Grade 2; ANSI/BHMA A156.39-2015 Residential Grade AAA; Available UL Listed for 3-hour fire door (F10, F40 (CSV Only), F51A, F80 functions).Latch: 1″x 2-1/4″, 1/4″ radius corner faceplate, 7/8″ housing diameter, 1/2″ throw, circular drive-in included, universal latchStrike: 1-5/8″ x 2-1/4″ radius corner, full lip, no boxBackset: Dual backset latches, fits either 2-3/8″ or 2-3/4″ backsetsCylinder: 5-Pin, C keyway, keyed alike (KA4)Door Range: 1-3/8″ 1-3/4″Keys: Two per lock, 5-pin, C sectionInstallation & OperationReview manufacturer specifications and verify door preparation requirements including door thickness, stile width, and handing as applicable to this product.Use manufacturer-provided templates to mark mounting hole locations accurately on door and/or frame surfaces.Prepare door and frame by drilling required holes and routing as specified in manufacturer instructions.Install all mounting hardware and secure the device to door and frame per manufacturer torque specifications.Adjust operational components for proper alignment, latching, and smooth operation throughout the full range of motion.Test device operation to verify proper function and make final adjustments as needed. Refer to manufacturer documentation for complete installation details and troubleshooting.Professional ApplicationsResidential Entry DoorsSingle-Family Home SecurityMulti-Unit Residential PropertiesApartment and Condominium UnitsTownhome and Duplex ApplicationsResidential Renovation ProjectsProperty Management InstallationsWhy Choose Schlage Residential Quality?Schlage Residential F51A locksets deliver professional-grade reliability with zinc and steel construction certified to ANSI/BHMA Grade 2 standards. The 10 Year warranty coverage provides added confidence for residential security applications. Engineered for demanding residential applications where dependable keyed entry performance is essential. ANSI/BHMA Grade 2 rated mechanical knob or lever with solid brass construction and SecureKey re-keyable cylinder. Support Resources: Manuals Hub: Schlage Manuals, Installation Guides & Templates (https://www.schlage.com/en/home/support/installation-manuals-templates.html) || Installation Guides: F-Series Knob and Lever Installation Instructions (https://www.schlage.com/content/dam/sch-us/documents/pdf/installation-manuals/P515-302.pdf) || Door Prep Templates: F10/F40/F51 Knob and Lever Door Prep Template (https://www.schlage.com/content/dam/sch-us/documents/pdf/installation-manuals/P513-593.pdf) || FAQs & Support: Schlage Product FAQs (https://www.schlage.com/en/home/support/faqs.html)