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Hydraulic Hinges Heavy Duty

4pcs Front Door Hinges | Self Closing | Soft Closing | Fire Rated | 4.5x4.5 | 8ft | 330 lbs | 1 ¾” Thick | SS304 | K51M-450-A4/B4

$532.80 - $608.80
$532.80
$532.80 - $608.80
$532.80
Color: Satin Stainless Steel-US32D
  • Material: Stainless Steel 304
  • Product Dimensions: 4.5"H × 4.5"W
  • Mounting Type: Door Mount – Full Mortise
  • Door Size: 1150mm W x 2440mm H (4ft x 8ft)
  • Door Weight: Min 40 lbs - Max 330 lbs
  • Door Thickness: 1 3/8” - 1 3/4”
  • Unit: 3 pieces
  • Warranty: 3-10 years

TALK TO SALES FIRST - NON REFUNDABLE

  • FEATURES
  • APPLICATIONS
  • DETAILS
  • SPECIFICATIONS
  • ADJUSTMENT

  • Product Description and Features

    • Fully adjustable closing force and speed according to environment needs
    • Numerical adjustment panel on hinge end to set up precise tension
    • Mechanical-only mechanism supporting heavy duty and fully exterior  
    • Aesthetically pleasing compared to door closers -- without extrusive arms 
    • UL-certified cycle testing ensures many years of low maintenance.

  • Applications

    • Hotel Rooms
    • Front Door
    • Commercial Entry Door
    • Residential Entry Door
    • Entrance Door
    • Exterior Entry Door
    • Exterior Wood Door
    • Steel Entry Door
    • Arch Top Front Door
    • 8ft Door
    • Heavy Duty
    • Interior & Exterior

  • Installation Kits  

    • Both machined #12-24 UNC ½”L and wooden tapping #12 x 1 ¼” screws included -- eight (8) of each type per hinge. Pack contains five (5) spares as well.
    • Three steel adhesive shims for gap adjustment between door and frame as needed
    • Tension Crook: Keeps hinge open during installation  
    • 5mm & 3mm hex allen wrenches  

  • Specifications

    Compliance Standards

    • ANSI A156.17 Grade 1 : one million cycle testing  
    • ANSI A156.7 Template Hinge : 6” x 6”
    • CSI Spec 08 7100 Door Hardware & 08 7808 Self-closing Hinges  
    • ADA Force : opening force no more than 5 lbs
    • ADA Closing Speed: at least 5 sec to move from m 90° to 12°
    • ADA Vertical Clearance: Does not intrude into the doorway as do some overhead closers

    Code note:

    Fire-rated doors cannot use hold-open features. 

    Waterson fire-rated soft-close garage door hinges are designed without hold-open, fully compliant with building and fire safety codes.

  • Adjustment Video

    Check the Full Adjustment Guidance here:
    English Version     
    Spanish Version 
adjustable self closing door hinges 4pcs Adjustable Self Closing Door inges | Mechanical | Fire Rated | 4.5x4.5 | 8ft | 330 lbs | 1 ¾” Thick | SS304 | K51M-450-A4
$532.80
soft close hinges for doors 4pcs Soft Close Hinges for Doors | Hydraulic | Fire Rated | 4.5x4.5 | 8ft | 330 lbs | 1 ¾” Thick | SS304 | K51M-450-B4
$573.80
Key Difference Mechanical self-closing Hydraulic hybrid soft-closing
Qty of Hinge 4 hinges/door (DS.SA.SA.SA1) 4 hinges/door (DS.SA.HA.SA)
Dimension 4.5"(H) x 4.5"(W) 4.5"(H) x 4.5"(W)
Self Closing o o
Fluid Motion x o
Hold Open x x

FAQ

Do I need to prepare anything before installing Waterson hinges?

Waterson hinges are built for hassle-free installation, but we still suggest reading through our installation guide beforehand. You can find it on our Installation page.

How can I adjust the tension?

Our hinges feature a clearly marked tension panel for quick and simple adjustments. For full guidance, please refer to the Adjustment page.

What’s included in the warranty?

The warranty covers any material or manufacturing defects. It doesn’t apply to issues caused by shipping, impact, improper storage, or misuse. For full terms, visit our Warranty page.

How do I get a quote for bulk orders?

Just leave your request on our Request Quotation page, and our team will reach out within 12 hours. Need help right away? Give us a call.

Where are products shipped from?

Most of our orders ship from warehouses in Michigan and California.
For urgent or high-volume orders, we may also ship directly from our Taiwan headquarters. FedEx or UPS handles most deliveries (1–5 business days), while large-volume orders go by ocean freight (30–60 days).

What’s the delivery time?

Once your payment is confirmed, shipping usually takes 3–5 business days, depending on your region.

How is the shipping fee calculated?

Shipping costs depend on domestic courier rates and the weight of your package. Since we ship within the U.S., charges are typically standard.

How do I track my shipment?

We’ll send a confirmation email with a tracking number after your order ships. You can use this number to follow the delivery progress.