Marks USA MAR5SS55N 5SS55N Ins...
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$1,281.01
$725.21
Marks USA 5SS55N Institutional Anti Ligature Passage Mortise Lockset - Keyless

Marks USA MAR5SS55N 5SS55N Institutional Anti-Ligature Passage Mortise Lockset with Solid Stainless Steel Trim, Keyless

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Model: 5SS55N-32D
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$1,281.01
$725.21
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Marks USA 5SS55N Institutional Anti-Ligature Passage Mortise Lockset with Solid Stainless Steel Trim, Keyless

The Marks USA 5SS55N is a heavy-duty institutional anti-ligature passage mortise lockset engineered for demanding commercial environments where safety and durability are paramount. Designed for keyless passage function (ANSI Function F75), the latch is retracted by knobs or levers at all times, making it ideal for high-traffic corridors, healthcare facilities, and institutional settings. Built to a 1-3/4" standard door thickness with a 2-3/4" backset, this lockset meets or exceeds all operational and security tests of ANSI A156.13-2005 for Series 5000, Grade 1, and is rated for a minimum of 1,500,000 life cycles. Solid stainless steel construction throughout ensures long-term performance in the most rigorous applications.

Key Features

  • Exceptional Durability: Life tested to a minimum of 1,500,000 cycles, ensuring long-term reliability in high-traffic institutional and commercial applications.
  • Anti-Ligature Safety Design: Solid stainless steel interior and exterior tapered knobs or levers recessed into thru-bolted roses, featuring safety knobs with recessed grip and finger indents (Patent #D587556) to minimize ligature risk.
  • Solid Stainless Steel Construction: Solid cast stainless steel levers, solid stainless steel cylinders with solid stainless steel security collars, and a solid stainless steel latch with antifriction latch lever for superior corrosion resistance and durability.
  • Precise Lock Specifications: 2-3/4" backset; adjustable bevel steel backplate measuring 1-1/4" x 8" x 7/64" thick; 3/4" reversible latch throw; 1/2" reversible auxiliary deadlatch throw; cover plate 1/16" thick with tamper-proof screws.
  • Tamper-Resistant Strike: Includes a 4-7/8" curved lip stainless steel strike secured with tamper-proof screws for added security and resistance to forced entry.
  • ADA-Compliant Lever Operation: Safety lever for handicapped access on clutch-operated mortise lock; levers rotate up and down freely in both locked and unlocked positions for accessible, ergonomic operation.
  • Robust Internal Components: Stamped steel case 3/32" thick with zinc dichromate finish; steel hubs (9/32" on diamond, 5/16" on square) with security separator; steel hub lock arm 1/8" thick; independent spring-loaded spindles for reliable, consistent operation.
  • Standard Door Preparation: ANSI A115.1 lock face cutout with 2-1/8" through hole for knob/rose assembly; front size 1-1/8" x 2-1/4" for straightforward installation on standard commercial doors.

Certifications & Compliance

  • ANSI/BHMA A156.13-2005 Series 5000, Grade 1 — Meets or exceeds all operational and security tests
  • ANSI/BHMA Certified
  • UL Listed
  • ADA Compliant
  • ANSI Function F75 (Passage/Hall/Closet — Latch retracted by knobs/levers at all times)

Technical Specifications

  • Series: 5SS19 Series
  • Latch Throw: 9/16"
  • Product Group: Mechanical Locks
  • Product Subgroup: Bored Locksets
  • Product Type: Cylindrical Locks
  • Subcategory: Cylindrical Locks
  • ANSI/BHMA: ANSI/BHMA, UL Listed
  • Commercial/Residential: Commercial
  • Lock Type: Cylindrical
  • Function Description: Latch retracted by knobs/levers at all times
  • Front Size: 1-1/8" x 2-1/4"
  • ADA Compliant: Yes
  • Keyed: No
  • ANSI Function: F75
  • Product Attribute: Cylindrical Locks
  • Product Function: Passage/Hall/Closet
  • Latch Type Specification: Deadlocking
  • Product Category: Mechanical Locks
  • Department: Door Hardware

Typical Applications

  • Healthcare and Behavioral Health Facilities
  • Institutional and Correctional Environments
  • Educational Facilities and Schools
  • Commercial Office Buildings
  • Government and Municipal Buildings
  • Multi-Tenant Residential and Assisted Living Properties
  • High-Traffic Corridors and Common Areas

Why Marks USA 5SS55N?

Marks USA 5SS55N mortise locksets are built to the highest institutional standards, combining solid stainless steel construction throughout with a life test rating of 1,500,000 cycles minimum and full compliance with ANSI A156.13-2005 Grade 1 requirements. The anti-ligature design — featuring patented recessed safety knobs (Patent #D587556), thru-bolted roses, and tamper-proof hardware — makes this lockset the trusted choice for professionals specifying door hardware in safety-critical commercial and institutional environments.

Manufacturer Resources

Marks USA Product Catalog

Product Specs

Series:
5SS19 Series
Latch Throw:
9/16"
Grade:
Grade 1
Product Group:
Mechanical Locks
Product Subgroup:
Bored Locksets
Product Type:
Cylindrical Locks
Subcategory:
Cylindrical Locks
ANSI/BHMA:
ANSI/BHMA, UL Listed
Commercial/Residential:
Commercial
Lock Type:
Cylindrical
Function Description:
Latch retracted by knobs/levers at all times
Front Size:
1-1/8” x 2-1/4”
ADA Compliant:
Yes
Keyed:
No
ANSI Function:
F75
Product Attribute:
Cylindrical Locks
Product Function:
Passage/Hall/Closet
Latch Type Specification:
Deadlocking
Product Category:
Mechanical Locks
Backset (Distance):
2-3/4"
Department:
Door Hardware

Marks USA 5SS55N-32D – Frequently Asked Questions

1) Does the Marks USA 5SS55N anti-ligature lockset need a key, and what does the passage function actually do?
It is keyless. The 5SS55N is ANSI function F75, passage/hall/closet, so the latch is retracted by the knobs or levers at all times and there is no locking from either side. That makes it the right pick for corridors, day rooms, and closets where the door only needs to latch shut, not secure. If you need the room to lock, this is the wrong function.
2) What backset and door prep does the Marks USA 5SS55N require?
Standard commercial prep: 2-3/4 inch backset, ANSI A115.1 lock face cutout with a 2-1/8 inch through hole for the knob or rose assembly, and a 1-1/8 by 2-1/4 inch front. Door thickness is 1-3/4 inches. The strike is a 4-7/8 inch curved lip stainless strike with tamper-proof screws. If your existing openings are prepped 2-3/8 inch backset, this will not drop in.
3) Is the Marks USA 5SS55N handed, and can it go on either swing?
No handing to specify. The latch is reversible, and so is the auxiliary deadlatch, so one lockset covers left and right hand openings. The steel backplate is adjustable bevel, which lets it sit flat on a beveled edge door as well as a square one.
4) What makes the Marks USA 5SS55N anti-ligature, and is it suitable for a behavioral health unit?
The trim is what does the work. Interior and exterior knobs or levers are solid stainless, tapered, and recessed into thru-bolted roses, with a recessed grip and finger indents (patent D587556) so there is no protruding edge to tie off to. Tamper-proof screws hold the cover plate and the strike. That construction is what behavioral health, correctional, and assisted living specs are usually looking for on a passage opening.
5) Does the Marks USA 5SS55N meet Grade 1 and ADA for an institutional spec?
Yes on both. It is ANSI/BHMA A156.13-2005 Series 5000 Grade 1, ANSI/BHMA certified, and UL Listed. ADA compliant, with a clutch-operated safety lever for handicapped access that rotates freely up and down. Life tested to a minimum of 1,500,000 cycles, which is the number facilities people usually want in writing for a high-traffic corridor.
6) Will the Marks USA 5SS55N work on a 1-3/8 inch or 2 inch door?
No. The 5SS55N is built for a 1-3/4 inch door, which is the standard commercial thickness, and it is not a range product. For a thinner or thicker leaf you want something with a stated range, like the Cal-Royal CAL30 passage lockset at 1-3/8 to 2 inches or the Dorma CL701 passage lever in the CL700 Series.
7) What is the closest Grade 1 passage lockset to the Marks USA 5SS55N if anti-ligature trim is not required?
The Cal-Royal CAL30 Calypso is a Grade 1 extra heavy duty passage lockset covering the same Passage/Hall/Closet function as the Marks USA 5SS55N, and it accepts doors from 1-3/8 inch to 2 inch. The difference is the trim: the 5SS55N uses solid stainless steel tapered knobs or levers recessed into thru-bolted roses with patented finger-indent safety grips to reduce ligature risk, while the CAL30 is a conventional lever lockset. On a behavioral health or correctional opening, the anti-ligature trim is the reason to stay with the 5SS55N; on a general corridor or closet door, the CAL30 meets the same grade and function.
8) Is the Orca OCL210 a substitute for the Marks USA 5SS55N passage lockset?
Only where the spec allows a lighter duty lock. The Orca Hardware OCL210 is a passage cylindrical lockset rated Grade 2 and medium duty, while the Marks USA 5SS55N is Grade 1 and life tested to a minimum of 1,500,000 cycles with solid stainless steel construction throughout. Both give the same latch-retracted-at-all-times operation, so on a low-traffic interior closet or office door the OCL210 performs the function. On an institutional corridor carrying a Grade 1 line item, the OCL210 will not satisfy the submittal.
9) I need privacy, not passage, on a behavioral health bathroom door. What takes the place of the Marks USA 5SS55N?
The 5SS55N is ANSI Function F75, meaning the latch is retracted by the knobs or levers at all times with no locking at all, so it will not secure a bathroom. For a Grade 1 privacy function in the same cylindrical family, the Cal-Royal CAL20 Calypso is a Grade 1 extra heavy duty privacy lock for doors 1-3/8 inch to 2 inch, and the Orca OCL240 covers privacy at Grade 2 medium duty. Neither carries the recessed stainless anti-ligature trim of the 5SS55N, so confirm with the facility whether ligature-resistant trim is required on that opening before substituting.
10) What finish does the Marks USA 5SS55N come in?
One finish only: US32D satin stainless steel. That is consistent with the solid stainless construction throughout, including the levers, security collars, latch and strike, and it is the finish that holds up to cleaning chemicals and corrosion in healthcare and correctional work. If your building standard is oil rubbed bronze or brass, this lockset will not match it.
11) I just need a Grade 1 passage lockset for an office corridor, not an anti-ligature one. What else is there?
If ligature resistance is not part of the spec, the Cal-Royal CAL30 Calypso is a Grade 1 extra heavy duty passage lockset that covers 1-3/8 to 2 inch doors, so it suits a building with mixed door thicknesses. For lighter traffic, the Orca Hardware OCL210 is a medium duty Grade 2 passage cylindrical lockset. The 5SS55N is worth the money specifically where you need the recessed anti-ligature trim and solid stainless build.
12) Is the strike included with the Marks USA 5SS55N, or do I order it separately?
The strike ships with it. You get a 4-7/8 inch curved lip stainless steel strike fastened with tamper-proof screws. If your frames are already prepped for a 4-7/8 inch ANSI strike, the existing cutout carries over.
13) Can I standardize a whole floor on the Marks USA 5SS55N?
For passage openings, yes, and that is what it is built for. One finish (US32D satin stainless), no handing to track, one door thickness (1-3/4 inch), and one backset (2-3/4 inch) means every corridor and closet door orders the same way. Where a room needs privacy or keyed entry you will have to pair it with a different function from the same trim family to keep the look consistent.
14) The opening needs to be keyed. What do I order instead of the Marks USA 5SS55N?
The 5SS55N is keyless by design, so there is no cylinder to key. For a keyed cylindrical lock at the same Grade 1 level, the Dorma C150 is a Grade 1 heavy duty entry/office cylindrical lock for doors 1-3/8 inch to 2-1/4 inch, and the Dorma C853 is a Grade 1 single cylinder entrance lever lockset over the same thickness range. The Orca OCL250 covers entrance function at Grade 2 medium duty where a lighter lock is acceptable.
15) Can I use a Lockey 2830 mechanical pushbutton lock where the Marks USA 5SS55N is specified?
They are not equivalent. The Lockey 2830 is a mechanical pushbutton keyless knob lock with an auto-locking passage function that fits doors 1-1/8 inch to 2 inch, so it adds code entry without batteries but uses a protruding pushbutton knob. The Marks USA 5SS55N is a Grade 1 keyless passage lockset with solid stainless steel recessed anti-ligature trim, a 2-3/4 inch backset, and a 4-7/8 inch curved lip stainless strike with tamper-proof screws. Where the spec is driven by ligature resistance or a Grade 1 institutional requirement, the 2830 is not a swap.
16) Which passage option should I use on a 2 inch thick door, since the Marks USA 5SS55N is built for 1-3/4 inch?
The Marks USA 5SS55N is built to a 1-3/4 inch standard door thickness. Where the leaf is thicker, the Cal-Royal CAL30 Grade 1 passage lockset covers 1-3/8 inch to 2 inch, the Dorma CL701 is a Grade 2 non-keyed lever in passage function, and the Lockey 2830 passage knob covers 1-1/8 inch to 2 inch. None of those carries the recessed stainless anti-ligature trim, so on a behavioral health opening confirm the door thickness with the manufacturer rather than substituting away from the 5SS55N.
17) Does the Marks USA 5SS55N latch stay put if someone pushes on the door edge?
Yes. It uses a deadlocking latch with an auxiliary deadlatch, so once the door is closed the latchbolt is deadlocked against being shimmed or loided. The latch itself is solid stainless with an antifriction latch lever, which keeps it operating cleanly on doors that are out of square or seeing constant use.
How fast can I get the Marks USA 5SS55N-32D delivered?
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Can I return it if it doesn’t work for me?
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Does the Marks USA 5SS55N-32D come with a warranty?
Absolutely. The Marks USA 5SS55N-32D is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Marks USA 5SS55N-32D?
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