Commercial 4 1/2 Inches Door Hinges
Stainless Steel Self Closing

Waterson’s commercial 4 1/2 door hinges are durable and versatile, designed for high-traffic areas and fire-rated doors. Fully adjustable, the 4 1/2 hinges provide precise control over closing speed and backcheck, ensuring smooth operation. Made from high-quality materials, these hinges are built to withstand frequent use and comply with ADA standards for speed control, closing force, and door clearance.

HOW TO ORDER

Most Frequently Asked Questions

What features make Waterson 4.5 door hinges stand out?

Speed control, low opening force, weather resistance, hold open, heavy-duty, and more. Learn about our 7 innovative features.

What are the differences between Mechanical Self-Closing hinges and Hydraulic Hybrid Soft-Close hinges?

Read about the differences of Mechanical Only Self Closing and Hydraulic Hybrid Soft Close differences.

How does the self-closing mechanism of Waterson 4.5 door hinges operate?

Understand the self-closing hinges mechanism.

Waterson 4.5 Inch Commercial Hinges Type Table

Each hinge has two distinct functions, one adjusted from the hinge top, and the other from the bottom. Note: Waterson hinges are non-handed and can be inverted.

Hinge TYPE	MECHANISM	FUNCTIONS
DS	Top: Spring Power Bottom: Spring Power	Dual door closing force
SA1	Top: Spring Power Bottom: Mechanical Friction	Door closing force & latch speed control
SA	Top: Spring Power Bottom: Mechanical Friction	Door closing force & swing speed control
SB	Top: Spring Power Bottom: Hold-open Feature	Door closing force & hold the door at 85°+/-5°
HA	Top: Hydraulic Damping Bottom: Mechanical Friction	Both swing & latch speed control depends on settings
HS	Top: Hydraulic Damping Bottom: Spring Power	Door closing force & both swing & latch speed control depends on settings

FULL MORTISE 4-1/2 x 4-1/2 HINGES

FULL MORTISE 4-1/2 x 4-1/2 HINGES

A Waterson Hinges Set contains 2-3-4 hinges. Each hinge provides a specific and distinct function that contributes to the set’s optimal performance.

Door Size	Product SKU Full mortise 4.5*4.5	FEATURES (Door Range ≤ 120°)			Closing Type Mechanical Only – M Hydraulic Hybrid – H	Hinge Qty Hinge Type	Finish
Door Size	Product SKU Full mortise 4.5*4.5	Self-closing	Fluid Motion	90°Hold-open	Closing Type Mechanical Only – M Hydraulic Hybrid – H	Hinge Qty Hinge Type	Finish
1-3/4″ < 6’-0 x 4′-0≤ 150 lbs	K51M-450-A2	●			M	2 hinges/door (SA.SA1)	In Stock 630(US32D)-Satin Brushed 631(US19)-Flat Black-Powder Coating Special Order 695-Dark Satin Bronze-Powder coating 731(US4)-Satin Brass-Physical vapor deposition 612(US10)-Satin Bronze-Physical vapor deposition White Custom order
1-3/4″ < 6’-0 x 4′-0≤ 150 lbs	K51M-450-B2	●	●		H	2 hinges/door (DS.HA)
1-3/4″ < 7’-0 x 4′-0≤ 260 lbs	K51M-450-A3	●			M	3 hinges/door (SA.SA.SA1)
	K51M-450-B3	●	●		H	3 hinges/door (DS.HA.SA1)
	K51M-450-C3	●		●	M	3 hinges/door (SB.SA.SA1)
	K51M-450-D3	●	●	●	H	3 hinges/door (DS.HA.SB)
1-3/4″ < 8’-0 x 4′-0≤ 260 lbs	K51M-450-C4	●		●	M	4 hinges/door (SA.SB.SA.SA1)	Other Options
1-3/4″ < 8’-0 x 4′-0≤ 260 lbs	K51M-450-D4	●	●	●	H	4 hinges/door (DS.SB.HA.SA1)	WP01: 90° door stop WP02: 120° door stop 316: Stainless steel R14: 1/4″ Radius Corners R58: 5/8″ Radius Corners
1-3/4″ < 8’-0 x 4′-0≤ 330 lbs	K51M-450-A4	●			M	4 hinges/door (DS,SA,SA,SA1)
1-3/4″ < 8’-0 x 4′-0≤ 330 lbs	K51M-450-B4	●	●		H	4 hinges/door (DS.SA.HA.SA1)

Please contact us directly concerning doors over the above specifications.

We provide additional door stop ( at 90° or 120°) features for all models.
Door Stop Options: A) two hinge set requires one door stop; B) three-four hinge set requires two door stops. Click here to see the drawing.

DOWNLOAD TABLE HERE

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Case Studies

Various businesses, including hotels, schools, and retail stores, choose Waterson self-closing 4 1/2 door hinges for durability, design, and sustainability.

Palm House Hotel

84 doors in the hotel are equipped with our heavy-duty self-closing hinges.

✓ ADA compliant
✓ Low maintenance
✓ 3-hour fire resistance

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Loft Apartment LA

FLOR 401 Lofts chose Waterson to provide suitable aesthetic self-closing hinges.

✓ Speed adjustment
✓ ADA heavy-duty
✓ Adjustable closing force

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Moreno Elementary School

A solution for low-headroom doors and an upgrade from protruding closer arms.

✓ Corrosion-free
✓ high strength
✓ Ensure safety

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ROSS Store USA

Thousands of fitting room doors feature our self-closing hinges for durability and style.

✓ Controllable force
✓ fluid motion
✓ Easily adjustable

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Catalog

US AREA
Full Mortise 4 1/2 Hinge Catalog – Waterson Stainless Steel Self-closing Hinge – For Commercial Door – US AREA			Download
NON-US AREA
Full Mortise 4 1/2 Hinge Catalog – Waterson Stainless Steel Self-closing Hinge For Commercial Door – NON-US AREA			Download

Technical Drawing for 4,5″ x 4,5″

US AREA
Full Mortise Self-closing Hinge – Stainless Steel – Commercial Grade – 4-1/2″x 4-1/2″ (K51M-450)	PDF	DWG	X_T
Full Mortise Self-closing Hinge – Stainless Steel – Commercial Grade – 4-1/2″ x 4-1/2″ -1/4 R (K51M-450-1/4R)	PDF	DWG	X_T
Full Mortise Self-closing Hinge – Stainless Steel – Commercial Grade – 4-1/2″ x 4-1/2″ -5/8 R (K51M-450-5/8R)	PDF	DWG	X_T

Code Compliance

ANSI/BHMA A156.7 Full Mortise Template
ANSI/BHMA A 156.17 Grade 1 Single Acting Hinge
ANSI/ICC A117.1 ADA Accessibility
UL Listed for ANSI/UL 10B and UL 10C, CAN/ULC S104 up to 3 hours
NFPA 80 National Fire Protection – Fire Door Assembly
NEPA101 National Fire Protection – Self Closing Device
ANSI/BHMA A 156.18 Finishes

Specify Waterson

Available for Download
How to Specify			Download
Data Sheet			Download
Warranty			Download
Guide Spec			Download
UL Report ( 8ft door )			Download
UL Report ( 7ft door, 3 hour fire-rated )			Download
SGS Report			Download
BSD Spec Link			Click Here

Installation and Adjustment Instructions

Waterson 4 1/2 Door Hinges are easily adjustable and re-adjustable simply with two Allen wrenches in just minutes. Follow our procedure to get the optimal closing experience.

Available for Download
Installation Guide			Click Here
Set A3 ( SA.SA.SA1 ) – Waterson self-closing hinge adjustment manual			Download
Set B3 ( DS.HA.SA1 ) – Waterson self-closing hinge adjustment manual			Download
Set C3 ( SB.SA.SA1 ) – Waterson self-closing hinge adjustment manual			Download
Set D3 ( DS.HA.SB ) – Waterson self-closing hinge adjustment manual			Download
Set A4 ( DS.SA.SA.SA1 ) – Waterson self-closing hinge adjustment manual			Download
Set B4 ( DS.HA.SA.SA1 ) – Waterson self-closing hinge adjustment manual			Download
Set C4 ( SB.SA.SA1.SA1 ) – Waterson self-closing hinge adjustment manual			Download
Set D4 ( DS.SB.HA.SA1 ) – Waterson self-closing hinge adjustment manual			Download

How to Adjust

Please note that Waterson offers a variety of product codes including K51M, K51SWRH, K51P, K51L, and K51GG, among others. However, the adjustment process remains consistent and is categorized based on codes A, B, C, and D. Below are the videos on how to adjust:

K51M-A3 (SA.SA.SA1)