Progressive Hardware Co., Inc.
Progressive Hardware Co., Inc. 2600 Polished Brass US3 Door Knob Set
Solid brass knob set with spindle fits Marks surface-mount mortise locksets and has served as a popular replacement for over 60 years
- Surface finishBright Brass
- Sold asEach
- Product typeDoor Knob
- Polished Brass US3 finish resists tarnish for lasting shine
- 2-1/4" solid brass knobs deliver substantial feel and durability
- Case-hardened set screws prevent loosening under daily use
- 3-1/2" straight spindle at 20 TPI fits Marks 91A and 71A mortise locksets
- Trusted replacement design used for over 60 years
Polished Brass US3 Door Knob Set
This solid brass knob set suits owners restoring period hardware or fitting Marks surface-mount mortise locksets such as the 91A and 71A models. The 2600 pattern has been the standard replacement for over 60 years and ships as one pair per box.
Straightforward installation with supplied spindle
A 3-1/2 inch straight spindle and case-hardened set screws are included, so no extra parts are needed for a typical Marks lockset. The spindle uses 20 TPI threading; verify that the existing lock body matches this pitch before fitting.
Comfortable fit for standard mortise doors
The 2-1/4 inch diameter knobs work with common door thicknesses found on Marks surface-mount mortise applications. Very thick or non-standard doors may exceed the spindle length and require a longer spindle not supplied in the box.
How it compares
Measured against everything we stock in Door Lock Sets & Deadbolts, at today’s prices. Recalculated every night.
- Price $19.99
- Cheaper than about 70% of the 2,145 comparable items (median $55.99).
Specifications
| Product | |
|---|---|
| Product type | Door Knob |
| Size & build | |
| Surface finish | Bright Brass |
Questions about this item
How do I verify the 2600 knob set is installed correctly on my Marks 91A mortise lockset?
After fitting the 2-1/4" diameter knobs with the supplied 3-1/2" straight spindle, operate the latch from both sides; smooth, binding-free motion and positive latch engagement confirm the 20 TPI threads are seated properly.
What comes in the box with the 2600 polished brass knob set and what must I supply myself?
One pair of solid brass knobs, case-hardened set screws and a 3-1/2" straight 20 TPI spindle are included; the Marks surface-mount mortise lockset body (91A, 71A or compatible) is not included and must be purchased separately.
Which version of the 2600 knob set should I choose for a Marks 71A versus a 91A lockset?
The same 2600 Polished Brass US3 set fits both the Marks 71A and 91A surface-mount mortise locksets; select this single model for either application.
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