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Polished brass mortise lockset with screw-on knobs and wide face plate, left hand

Tuff Stuff

Tuff Stuff 5100XL Polished Brass Left Hand Mortise Door Lock

SKU CH-FFEE-M4BF7 MPN 5100XL

Heavy-duty mortise entrance lockset with a wide face plate, solid brass construction and screw-on knobs for left-hand doors

  • Security gradeHeavy Duty
  • Location typeCommercial/Residential
  • Backset distance2-1/2 in
  • Lock keyingKeyed Different
  • Main functionEntrance
  • Surface finishPolished Brass
  • Heavy-duty security for commercial or residential doors with solid brass construction
  • Wide 1-1/4" x 8" face plate covers larger mortise cut-outs cleanly
  • Left-hand mortise configuration matches specific door swing requirements
  • Screw-on knobs with swivel spindle allow smooth operation and easy installation
  • Solid brass cylinder supplied with two keys provides reliable keyed-different access

Product Identity

This heavy-duty mortise entry lockset is built for commercial and residential doors that require a left-hand configuration. It features a solid brass cylinder supplied with two keys and a wide face plate measuring 1-1/4" x 8". The screw-on knobs use a swivel spindle for smooth operation.

Thermal Noise Power

As a mechanical locking device, this product generates no heat, consumes no electrical power and produces no audible noise during normal operation. Performance is entirely dependent on the precision of the solid brass components and the quality of the installation.

Sustained Load Behaviour

The wide face plate and solid brass construction are designed to withstand repeated daily use in high-traffic environments. The mortise mechanism maintains consistent deadbolt engagement and knob return over extended periods without electronic degradation or thermal throttling.

How it compares

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

Price $97.99
Pricier than about 65% of the 2,145 comparable items (median $55.99).

Specifications

Product
Brand nameEm-D-Kay
Product lineMarks 91A/3-X Like
Model name5100XL
Product typeMortise Entry Lock Set - Surface Mounted Screw-on Knobs
Design styleKnobs
Size & build
Surface finishPolished Brass
Main materialBrass
Backset distance2-1/2 in
More details
Security gradeHeavy Duty
Location typeCommercial/Residential
Lock keyingKeyed Different
Main functionEntrance

Questions about this item

How do I install the 5100XL mortise lock into a door and what step is commonly missed?

Mortise a pocket matching the 1-1/4" x 8" wide face plate, fit the lock body, secure the surface-mounted screw-on knobs on the swivel spindle, then fit the solid brass cylinder outside and thumb turn inside — the step often missed is aligning the spindle so both knobs turn freely after the case is screwed tight.

What maintenance or replacement will the 5100XL need over time?

Lubricate the bolt and latch mechanism periodically with graphite powder; the solid brass cylinder and its two keys can be re-keyed or replaced if wear makes operation stiff, and the screw-on knobs may need tightening if the swivel spindle develops play.

What is the first limit that appears when the 5100XL sees heavy daily traffic?

The 2-1/2" backset fixes the lever geometry, so sustained high-cycle use stresses the spindle and knob screws first — expect knob looseness or spindle wear before the brass case or deadbolt shows fatigue.

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