3-1/2 x 3-1/2 x 1/4 Radius Heavy Duty Spring Hinge, Pair, Bommer LB4311C-350
Packaged completed with a Pair (2) Single Action Spring Door Hinges, Tension Adjusting Tool, Locking Pins plus #10 x 3/4" Wood Screws and #10-24 x 1/2" machine screws. Utilizes ANSI template screw hole pattern for use with wood or metal doors.
Bommer spring hinges are UL Listed for fire door applications, certified Grade 1 (highest grade) for 1 million cycles and made in the USA. Pivot point aligns with residential butt hinges gage .123 to .134
The included Tension Tool is use to adjust spring tension. The Locking Pins hold the Spring in tension after it is set. These adjustable tension spring hinges allow you to determine how much closing force you apply to the door (how hard/fast the door self closes).
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Specifications for Bommer LB4311C-350 Spring Hinge
- Height: 3-1/2"
- Width: 3-1/2"
- Corners: 1/4" Radius
- Gauge of Metal: .130 (Heavy Duty)
- Number of Holes: 6
- Standard Template Hole Pattern
- Wood Screws: #10 x 3/4"
- Machine Screws: #10-24 x 1/2"
- Hinge Material: Durable Steel
- Adjustable Spring Torque
- Non-Handed
- UL Listed R-4667 653M for fire door applications.
- BHMA Certified Grade 1 for 1 million cycles.
- Full Mortise - ANSI K81071F
- Available Finishes: 4
- Bommer LB4311C-350 Dimensions Diagram (PDF)
*Sold as a pair (2 Hinges).
** This item is being discontinued. Very limited quantities available.