McKinney T4B3386 4-1/2 x 4-1/2 Five-Knuckle Heavy Weight Stainless Steel Full Mortise Butt Hinge with Concealed Ball Bearings

The McKinney T4B3386 is a full mortise, five-knuckle heavy weight butt hinge engineered for high-frequency, high-load door openings. Constructed from stainless steel with a leaf thickness of 0.180 in., this hinge delivers the durability and smooth operation demanded by commercial and institutional door assemblies. The T4B heavy ball-bearing option incorporates concealed ball bearings, reducing friction and wear over the life of the opening — making it a preferred choice wherever continuous, reliable door swing performance is required. At 4-1/2 x 4-1/2 inches, the T4B3386 is sized appropriately for heavier door leaves and frames that call for a full mortise hinge installation.

Institutional Grade Features & Benefits

• Five-Knuckle Heavy Weight Design: The five-knuckle configuration provides increased knuckle contact area compared to standard-weight hinges, distributing load more evenly and adding structural integrity across the full range of door swing.
• Concealed Ball Bearings (T4B Option): Ball bearings are fully concealed within the barrel, delivering quiet, friction-free operation that extends hinge service life even under high-cycle, heavy-load conditions.
• Heavy Weight Gauge — 0.180 in. Leaf Thickness: The 0.180 in. steel leaf thickness (per the McKinney full-line catalog) exceeds standard-weight hinge stock, providing greater resistance to deflection and door sag over time.
• Stainless Steel Construction: Stainless steel offers excellent corrosion resistance, making the T4B3386 well-suited for environments where moisture, humidity, or corrosive conditions may be a concern.
• Full Mortise Installation: Designed for full mortise application — both leaves are mortised into the door edge and frame, producing a clean, flush appearance and a mechanically sound connection.
• High-Frequency, High-Load Performance: The combination of heavy weight gauge, five-knuckle geometry, and ball-bearing action positions the T4B3386 for openings that see demanding, repetitive use.

Technical Details