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Polished brass mortise entry lockset with wide face plate and screw-on knobs

Marks USA

Marks USA 91A/3-X Polished Brass Right Hand Mortise Entry Door Lock

SKU CH-XMZN-8VC3H MPN 91A/3-X

Polished brass mortise entry lockset with 2-1/2" backset, surface-mounted wide face plate, screw-on knobs and solid brass cylinder

  • Backset distance2-1/2 in
  • Lock keyingKeyed Different
  • Main functionEntrance
  • Surface finishPolished Brass
  • Sold asBox
  • Product typeMortise Entry Surface Mounted Lockset with 1-1/4 in x 8 in W
  • Polished brass finish resists corrosion and matches traditional hardware
  • 1-1/4" x 8" wide face plate covers large door cut-outs cleanly
  • Solid brass cylinder with two keys provides reliable keyed entry
  • Right-hand mortise configuration fits standard entrance door preparations
  • Screw-on knobs with swivel spindle allow secure, smooth operation

Product Overview

The Marks USA 91A/3-X is a polished brass mortise entry lockset designed for right-hand doors. It features a surface-mounted configuration with a wide face plate measuring 1-1/4" x 8" and a 2-1/2" backset. The set includes screw-on knobs with a swivel spindle and a solid brass cylinder supplied with two keys. This hardware provides a traditional entrance function for commercial or residential openings.

Suitable Applications

This lockset suits installers fitting a right-hand mortise entrance where a wide face plate and surface-mounted brass trim are specified. The screw-on knob design allows straightforward attachment during installation. It is not suitable for left-hand door swings or for projects requiring a narrow face plate, an integrated rose design, or electronic access control. Buyers needing a different backset dimension should verify compatibility before ordering.

Critical Specification

The 2-1/2" backset is the single measurement that determines whether this lock aligns with the existing door preparation. An incorrect backset prevents the latch and deadbolt from engaging the strike plate correctly, making the hardware unusable for that opening. Confirm this dimension matches the door bore before purchase to ensure proper fit and function.

How it compares

Measured against everything we stock in Door Lock Sets & Deadbolts, at today’s prices. Recalculated every night.

Price $111.99
Pricier than about 68% of the 2,145 comparable items (median $55.99).

Specifications

Product
Brand nameMarks
Product lineMetro
Model name91A/3-X
Product typeMortise Entry Surface Mounted Lockset with 1-1/4 in x 8 in Wide Face Plate
Design styleKnobs
Size & build
Surface finishPolished Brass
Main materialBrass
Backset distance2-1/2 in
More details
Lock keyingKeyed Different
Main functionEntrance

Questions about this item

Which handing should I order for a door that swings inward on the right?

Choose the right-hand mortise lockset — it is built for doors hinged on the right when viewed from the outside.

What does the 2-1/2" backset mean once the lock is installed?

It places the centre of the knob and cylinder 2-1/2 inches from the door edge, so the bore must match that distance.

How does the surface-mounted face plate affect the door preparation?

The 1-1/4" x 8" brass plate fastens to the door face with screws, avoiding a deep mortise pocket.

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