Design Hardware DH-BB5-NRP-4.5X4.5 Full Mortise, Standard Weight, Ball Bearing Hinge

The Design Hardware DH-BB5-NRP is a full mortise, standard weight, five-knuckle ball bearing hinge in the 4.5" x 4.5" size, with a non-removable pin (NRP) for added security. A ball bearing hinge carries the door on sealed bearings between the knuckles, which lets it handle higher-frequency, higher-traffic doors than a plain bearing hinge, and the NRP feature means the pin can't be pulled out when the door is closed, important on out-swinging exterior doors where the hinge is accessible from the outside. It's steel or stainless, fire-door approved, and carries a limited lifetime warranty, a heavy-duty commercial hinge at a value price.

Ball bearing and NRP, and why they matter

This is worth understanding, because these two features define where the DH-BB5-NRP fits. Ball bearings are the key to a commercial hinge's longevity: each hinge has two sets of maintenance-free, non-detachable ball bearings that carry the door's weight smoothly and resist the wear that makes a plain-bearing hinge squeak and sag over time. That makes the ball bearing hinge the right choice for high-frequency and heavier doors, entrances, corridors, and any opening that cycles constantly.

The NRP (non-removable pin) is a security feature for out-swinging doors. On an out-swing, the hinge barrel faces the outside, so without protection an intruder could tap the pin out and lift the door off. The non-removable pin can't be backed out while the door is closed, defeating that attack. For exterior out-swinging doors, NRP is the standard spec, and the DH-BB5-NRP builds it in.

Built to commercial standard, fire-rated, electrification-ready

The DH-BB5-NRP meets ANSI A156.2 with dimensions and tolerances conforming to ANSI A156.7, in a .129 gauge. The base material is steel (ANSI A8112) or Grade 304 stainless (ANSI A5112), with marine grade 316 US32D stainless also available for corrosive or coastal environments. The five-knuckle design has templated hole locations for wood or metal doors and frames, a 1/16" swage gives 1/16" clearance between leaves, and the easily seated non-rising pin has a button head and plug for a finished look that stays put.

It's approved for most fire doors up to 4' x 10' singles and 8' x 10' pairs (refer to NFPA 80), and concealed thru-wire and monitoring options are available for electrified access-control openings. It ships in boxes of 3 hinges with a full set of machine and wood screws.

Design Hardware DH-BB5-NRP (4.5" x 4.5") specifications

• Type: Full mortise, five knuckle, ball bearing hinge. Standard weight. Non-removable pin (NRP).

• Size: 4.5" x 4.5".

• Bearings: 2 sets of maintenance-free, non-detachable ball bearings per hinge.

• Standards: Meets ANSI A156.2; dimensions/tolerances per ANSI A156.7. Gauge .129.

• Material: Steel (ANSI A8112) or Grade 304 stainless (ANSI A5112). Marine grade 316 US32D stainless available.

• Fire: Approved for most fire doors up to 4' x 10', 8' x 10' pairs (NFPA 80).

• Pin: Non-rising pin with button head and plug. NRP (non-removable).

• Swage: 1/16" (provides 1/16" clearance between leaves).

• Electrification: Concealed thru-wire and monitoring options available.

• Packaging: Boxes of 3 hinges with full machine and wood screw set.

• Warranty: Limited lifetime.

Why choose the Design Hardware DH-BB5-NRP

Design Hardware builds value-focused commercial hardware, and the DH-BB5-NRP gives you a genuine heavy-duty ball bearing hinge with security and fire-door credentials at a budget price. You get two sets of maintenance-free ball bearings for long life on busy doors, the non-removable pin for out-swing security, ANSI A156.2 compliance, fire-door approval, stainless and marine-grade options, and electrification readiness, all backed by a limited lifetime warranty. For exterior out-swinging doors and high-traffic openings that need a secure, durable hinge without premium-brand pricing, it's a smart choice.

One thing to confirm before ordering: this is the 4.5" x 4.5" standard-weight version with the non-removable pin. Verify your door size and weight (heavy or oversized doors may need heavy-weight hinges), confirm an out-swing application actually needs NRP, and choose steel, 304 stainless, or 316 marine stainless to match your environment. Other sizes (such as 4.5" x 4") and non-NRP versions are available if your opening differs.

Order the Design Hardware DH-BB5-NRP from American Locksets

We stock the Design Hardware hinge line from authorized distribution, so every hinge ships with the manufacturer warranty. Compare sizes and types in the Design Hardware 5 knuckle ball bearing category, see all five knuckle ball bearing hinges, or browse all door hinges.