Medeco 310100T M3 31 Series Large Format Interchangeable Core for Yale DL Keyway

Medeco 310100T M3 31 Series Large Format Interchangeable Core for Yale, DL Keyway

The Medeco M3 31 Series Large Format Interchangeable Core (LFIC) is a heavy-duty, Grade 1 commercial cylinder engineered to retrofit Yale LFIC mortise housings, rim, key-in-knob, and padlock bodies. Featuring the DL keyway and Medeco's M3 technology, this core allows non-technical personnel to quickly rekey locks using a special control key — no disassembly required. Constructed of durable machined brass components, the 31 Series positions its control/locking lug at the back of the cylinder, eliminating the need for build-up or control pins and simplifying integration into existing master key systems.

Key Features

• Tool-Free Core Changeability: Cores can be quickly and easily changed by non-technical personnel using a special control key, effectively "rekeying" the lock without disassembly — reducing the cost of routine rekeying service calls.
• 31 Series Control Lug Design: The control/locking lug is positioned at the back of the cylinder, activated by an extra-long key. This eliminates the need for build-up or control pins, simplifying pinning and enabling integration into existing master key systems not originally designed for interchangeable core pinning.
• UL437 Listed: Provides assurance that cylinders meet universal standards for drill and pick resistance and stand up to other types of forced attack.
• Yale LFIC Retrofit Compatibility: The 31 Series is specifically designed to retrofit Yale LFIC mortise housings, rim, key-in-knob, and padlock bodies for seamless upgrades to existing hardware.
• Machined Brass Construction: Cylinders are constructed of durable machined brass components, designed to last the life of your equipment in demanding commercial environments.
• Patented Key Control: Medeco 4 (M4) keys may only be duplicated by Medeco or an authorized Medeco service outlet, and only upon your request — providing superior key control and security.
• Flexible Keying Options: Locks can be keyed alike, keyed different, or master keyed depending on your specific security requirements.
• Wide Finish Selection: Available in 13 finishes including Bright Brass, Satin Brass, Antique Brass, Bright Bronze, Satin Bronze, Oil Rubbed Bronze, Bright Nickel, Satin Nickel, Antique Nickel, Black, Dark Bronze, Bright Chrome, and Satin Chrome.

Certifications & Compliance

• UL437 Listed — Drill and Pick Resistance Certified
• ANSI/BHMA Grade 1
• Heavy Duty Commercial Rating

Technical Specifications

• Series: 31 Series Large Format Interchangeable Core (LFIC)
• Cylinder Technology: Medeco M3
• Pinning: 6-Pin
• Keyway: DL Keyway
• Certification: ANSI/BHMA A156.5 Grade 1 rated hardware platform
• Construction: Solid brass construction with nickel-plated pins and hardened stainless-steel drill-resistant pins
• Compatibility: Retrofits into existing LFIC-prepped hardware without replacement
• Warranty: 2-year manufacturer's warranty

Typical Applications

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

Why Medeco?

Medeco M3 31 Series LFIC cylinders deliver professional-grade security through durable machined brass construction, UL437-listed drill and pick resistance, and a patented key control system that restricts unauthorized key duplication. The back-of-cylinder control lug design simplifies pinning and master key integration, making the 31 Series an ideal choice for demanding commercial applications where reliable, manageable access control is essential.