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Marks USA

Marks USA 3/26D Satin Chrome US26D Series 3 Mortise Armored Deadlock Body Brass 2-3/4" BackSet door lock

SKU CH-D4SJ-C69AP

A mortise armored deadlock body with brass construction and a 2-3/4 inch backset, supplied with strike plate 4035

  • Selling UnitBox
  • TypeDeadbolts
  • Backset2-3/4"
  • Satin Chrome US26D finish resists corrosion and wear
  • 1" bolt throw secures the door deep into the frame
  • Stamped steel case protects the mechanism from forced entry
  • 2-3/4" backset fits standard commercial door preparations
  • Series 3 mortise armored body adds strength for heavy use

Mortise Armored Deadlock Body

This Marks USA Series 3 mortise armored deadlock body is built for commercial and heavy-duty residential doors. It fits a standard 2-3/4 inch backset preparation and includes the #4035 strike in the box. The 1 inch bolt throw engages deeply into the frame for strong resistance against forced entry. A stamped steel case protects the internal mechanism from impact and wear.

Satin Chrome US26D Finish

The satin chrome US26D finish suits modern office corridors, retail entrances and apartment common areas where a clean, low-glare appearance is required. It coordinates with common lever trim and exit devices already specified in the hardware schedule. Buildings that need a bright polished chrome or an oil-rubbed bronze look should select a different finish code. The front plate measures 1-1/16 by 4-5/8 inches to cover standard mortise pockets.

Brass Construction With Steel Case

The lock body is machined from solid brass with a stamped steel case, combining corrosion resistance with structural rigidity. This material pair handles high-cycle traffic without the binding common in all-steel bodies exposed to humidity. Installers who need a non-metallic or composite body for magnetic environments must choose an alternative product. The box contains the lock body and the #4035 strike only.

Highlights

  • Satin Chrome US26D finish resists corrosion and wear
  • 1" bolt throw secures the door deep into the frame
  • Stamped steel case protects the mechanism from forced entry
  • 2-3/4" backset fits standard commercial door preparations
  • Series 3 mortise armored body adds strength for heavy use

Specifications

Selling UnitBox
TypeDeadbolts
Backset2-3/4"

Questions about this item

How much power does the Marks Series 3 mortise deadlock draw when it is engaged all day?

This mechanical deadlock uses no electricity, so it draws zero power and generates no heat or noise during continuous use.

What additional hardware must I already have to install the Marks 3/26D mortise deadlock body?

You need a mortise pocket cut to 1-1/16" X 4-5/8", a 2-3/4" backset bore, and a cylinder, trim and thumb-turn — none are included with the lock body.

Will the 1" bolt throw on this Marks deadlock align with the strike plate on my older mortise door prep?

The included #4035 strike is sized for the 1" throw; if your existing prep uses a different strike, you must replace it with the supplied one for proper engagement.

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