Medeco 200503 6-Pin Key-in-Knob Cylinder for Yale 5300LN, 5400LN & 4300 Series Knobs

Medeco 200503 6-Pin Key-in-Knob Cylinder for Yale 5300LN, 5400LN & 4300 Series Knobs

The Medeco 200503 is a 6-pin Key-in-Knob/Lever retrofit cylinder engineered to replace cylinders in Yale 5300LN, 5400LN, and 4300 Series knob-type and lever-type cylindrical locksets, as well as padlocks and bored-type auxiliary deadlatches and deadlocks. Constructed of durable machined brass components, this Medeco M4 cylinder delivers UL437-listed drill and pick resistance along with utility patent-pending key control, making it a high-security upgrade for commercial door hardware. Certified to ANSI A156.30 Level A for patent-protected key control and physical strength, and ANSI A156.5 Grade 1 for consistent quality in heavy-use applications, the 200503 is a trusted solution for facilities requiring superior access control.

Key Features

• High-Security 6-Pin Configuration: Six-pin cylinder design provides enhanced pick resistance and key control for demanding commercial security applications.
• UL437 Listed: Medeco M4 Key-in-Knob cylinders are UL437 listed for drill and pick resistance, delivering verified high-security performance.
• Patent-Pending Key Control: Utility patent-pending key control technology restricts unauthorized key duplication, protecting access integrity over the life of the installation.
• Machined Brass Construction: Cylinders are constructed of durable machined brass components for long-lasting reliability in high-traffic commercial environments.
• Broad Retrofit Compatibility: Designed to retrofit Yale 5300LN, 5400LN, and 4300 Series knob and lever cylindrical locksets, padlocks, and bored-type auxiliary deadlatches and deadlocks — reducing the need for full lockset replacement.
• Wide Finish Selection: Available in 14 finishes including Bright Brass (05), Satin Brass (06), Antique Brass (09), Satin Brass Blackened (10), Bright Bronze (11), Satin Bronze (12), Oil Rubbed Bronze (13), Bright Nickel (18), Satin Nickel (19), Antique Nickel (20), Black (22), Dark Bronze (24), Bright Chrome (25), and Satin Chrome (26).
• Industry-Leading Retrofit Range: Medeco offers over 100 different cylinder designs and tailpiece configurations, providing the largest retrofit capability in the industry and minimizing full lockset replacements.

Certifications & Compliance

• UL437 Listed — Drill and Pick Resistance (Medeco M4)
• ANSI A156.30 Level A — Patent-Protected Key Control and Physical Strength (M4, M3)
• ANSI A156.5 Grade 1 — Consistent Quality for Heavy-Use Applications (M4/M4 BiLevel, M3)

Technical Specifications

• Product Family: Key-in-Knob/Lever Cylinder
• Pinning: 6-Pin
• Compatible Hardware: Yale 5300LN 5400LN 4300 Series Knobs
• Certification: UL 437 Listed; ANSI/BHMA A156.30 (M4); ANSI/BHMA A156.5 Grade 1 (M4)
• Construction: Durable machined brass components
• Warranty: 2-year manufacturer's warranty

Typical Applications

• Commercial Office Buildings
• Educational Facilities
• Healthcare Institutions
• Government and Municipal Buildings
• Retail Establishments
• Industrial and Warehouse Facilities
• Multi-Tenant Residential and Mixed-Use Properties

Why Medeco?

Medeco Key-in-Knob cylinders are built from durable machined brass components and certified to both ANSI A156.30 Level A and ANSI A156.5 Grade 1, ensuring patent-protected key control and consistent performance under heavy commercial use. With UL437 listing for drill and pick resistance and over 100 retrofit configurations available, the Medeco 200503 delivers professional-grade security and unmatched installation flexibility for facilities that cannot compromise on access control.