The Schlage N123-086 is the OEM push button plunger bar assembly for the Schlage ND Series Grade 1 cylindrical lock family. It's the internal bar component that transmits the push button action from the inside lever to the chassis locking mechanism. When an occupant presses the interior button on a privacy, office, or corridor lock, this plunger bar is what physically engages and holds the lock in the locked state. If the plunger cracks, wears out, or loses engagement, the push button function stops working completely. The outside lever can no longer be locked from inside, and in privacy function locks, the occupancy indication fails as well.

The N123-086 is the updated version that replaced the N123-028. The newer design is approximately 0.1 inches longer with a smooth shaft profile, improving engagement consistency across the ND Series chassis variants. For any ND Series lock manufactured after February 2017, N123-086 is the correct plunger bar to order.

Which Schlage ND Series Locks Use the N123-086?

This plunger bar assembly is confirmed in the official Schlage ND Series service manual for seven functions. It serves the ND30 patio lock, the ND40 bath/bedroom privacy lock, the ND44 hospital privacy lock, the ND50 entrance/office lock, the ND73 corridor lock, the ND91 Vandlgard entrance/office lock, and the ND97 Vandlgard corridor lock. The ND52 keyed privacy lock and related functions in the ND Series privacy/keyed access family also share this component type across the push-button locking chassis.

Across all these functions, the N123-086 is listed as part "R" in the service manual trim assembly diagrams, designated as "Plunger assembly - push button" and sitting between the visible push button on the inside lever and the internal slide mechanism in the lock chassis.

How the Push Button Plunger Bar Works in ND Series Locks

In privacy lock functions like the ND30, ND40, and ND44, pushing the inside button drives the plunger bar forward to engage a catch in the chassis. That catch holds the outside lever in the fixed, inoperative position. Closing the door or rotating the inside lever releases the catch, retracting the plunger and restoring the outside lever to free operation. In the ND44 hospital privacy lock, an emergency outside button overrides the plunger engagement without a key, which is the life-safety requirement in clinical settings.

In keyed functions like the ND50, ND73, ND91, and ND97, the push button drives the same plunger into a locked position that holds the outside lever fixed. The outside key or inside lever rotation releases it. In corridor (ND73/ND97) and entrance (ND50/ND91) functions, this gives the occupant a one-touch way to secure the opening from inside without requiring a key.

Why the Plunger Bar Fails and When to Replace It

On high-traffic ND Series installations, the push button function is activated dozens to hundreds of times daily. The plunger bar takes the full mechanical load of every button press across a shift. Common failure modes include wear on the catch engagement surfaces, stress cracking along the bar body, and loss of the spring-return tension that allows the plunger to disengage cleanly when the door closes. Any of these result in a button that either won't engage at all, gets stuck in the locked position, or won't fully release.

Because the N123-086 is a field-replaceable trim component, installation doesn't require removing the lock chassis from the door. The trim assembly on the inside lever disassembles to expose the plunger bar, which is removed and replaced without disturbing the latch or chassis in the door prep. For facilities stocking replacement parts for an ND Series installation, keeping this part on the shelf eliminates service calls that would otherwise require ordering and waiting.

For the full Schlage ND Series parts catalog, SecurityParts stocks chassis kits, spring cages, levers, and related trim components across all functions.