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Polished brass mortise lockset with lever handle and double cylinder, left hand orientation

Marks USA

Marks USA 2750C/3 Polished Brass Left Hand Mortise Double Cylinder Door Lock

SKU CH-XS02-Z6TR1 MPN 2750C/3

A slim-profile mortise lockset with a 1-inch backset, double-cylinder keying and thru-bolted brass lever trim for left-hand steel security doors

  • FinishPolished Brass
  • Selling UnitBox
  • TypeMortise Lockset
  • FeaturesThinline Slim Line Lockset
  • MaterialBrass
  • Backset1 inch
  • Thinline Slim Line design fits narrow door stiles
  • Polished brass finish resists corrosion and adds traditional style
  • Double cylinder function requires a key on both sides for controlled access
  • 1-inch backset matches standard mortise lock preparations
  • Thru-bolted solid brass trim with spring-loaded self-adjusting spindles ensures secure lever attachment

Polished Brass Mortise Lockset

The Marks USA 2750C/3 is a Thinline Slim Line mortise lever entry lockset finished in polished brass. It uses a double cylinder mechanism that requires a key on both the interior and exterior sides. The lock is configured for left-hand door operation and suits commercial steel security or storm doors.

Check Door Handing And Backset

Verify that the door swings left-hand before ordering because the trim is handed and not reversible. Confirm the mortise pocket accepts a one-inch backset and that the lock face plate measures one inch by nine and seven sixteenths inches. Ensure the existing through-bolt mounting holes align with the eight and one quarter inch spacing.

Double Cylinder Security And Lever Operation

The double cylinder function frees you from interior thumb-turn operation but requires a key for egress, so check local fire-code requirements. Solid brass lever plates are through-bolted for strength and use spring-loaded self-adjusting spindles with screwless levers. The set includes the mortise body, face plate, lever trim and cylinders for a complete installation.

Highlights

  • Thinline Slim Line design fits narrow door stiles
  • Polished brass finish resists corrosion and adds traditional style
  • Double cylinder function requires a key on both sides for controlled access
  • 1-inch backset matches standard mortise lock preparations
  • Thru-bolted solid brass trim with spring-loaded self-adjusting spindles ensures secure lever attachment

Specifications

BrandMarks
Model2750C/3
FinishPolished Brass
Selling UnitBox
TypeMortise Lockset
FeaturesThinline Slim Line Lockset
MaterialBrass
Backset1 inch
KeyingKeyed Different
StyleLever
Series2750C
FunctionDouble Cylinder

Questions about this item

Does the box include the double cylinder and both keys, or must the cylinder be purchased separately?

The lockset ships as a complete assembly with the double cylinder installed and two keys supplied; no separate cylinder purchase is required.

How do I choose between the left-hand and right-hand versions of the 2750C/3?

Select the left-hand model when the hinges are on the left as you face the door from outside; choose the right-hand version for the opposite swing.

What does the 1-inch backset mean when the lock is fitted to a steel security door?

It positions the spindle centre 1 inch from the door edge, matching the standard prep cut on most steel security and storm doors.

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