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Great Lakes Window Sliding Door 3-Point Lock – 1" Backset, Discontinued

Great Lakes Window Sliding Door 3-Point Lock – 1" Backset, Discontinued

SKU: 4991830

  • Compatibility: Replacement for Great Lakes Window (GLW) vinyl sliding glass patio doors with 3-point lock
  • Lock Style: Multi-point lock with one hook at handle and two vertical locking rods
  • Backset: 1" (25.4mm)
  • Door Thickness: Original door was 2" (50.8mm) thick
  • Cylinder Type: 70mm Italian Euro/Profile cylinder
  • Lower Rod: 34-1/2" (876.3mm), 1/4" diameter
  • Upper Rod: 47-3/4" (1212.9mm), 1/4" diameter
  • Lock Cover Plate: Aluminum, 1-3/4" x 11-3/4" (44.5mm x 298.5mm) with 4 mounting holes
  • Status: Original lock discontinued; replacement available with minor modifications
Discontinued - See Replacement Options
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GLW Sliding Door 3-Point Lock Replacement (4991830)

This listing provides replacement information for the discontinued Great Lakes Window (GLW) vinyl sliding glass patio door 3-point lock system. The original lock featured a multi-point design with one hook at the handle location and two vertical locking rods for enhanced security.

The original Great Lakes Window sliding door was 2 inches thick and utilized a 70mm Italian Euro/Profile cylinder. The door was available with three different handle styles, each with different bore configurations. Solid brass handles were paired with keyed cylinders, while plated brass handles were offered with or without keyed cylinders. Painted gold and wood grain handles were not available with key options.

Technical Information

  • Backset: 1 inch (25.4mm)
  • Door Thickness: 2 inches (50.8mm)
  • Cylinder Type: 70mm Italian Euro/Profile
  • Lower Rod Length: 34-1/2 inches (876.3mm), 1/4 inch diameter
  • Upper Rod Length: 47-3/4 inches (1212.9mm), 1/4 inch diameter
  • Lock Cover Plate: Aluminum, 1-3/4 x 11-3/4 inches (44.5 x 298.5mm) with 4 mounting holes

Notes

  • Original lock has been discontinued
  • Replacement option available with minor modifications required
  • Solid brass handles used with keyed cylinder
  • Plated brass handles available with or without keyed cylinder
  • Painted gold and wood handles were not available with key option

Replaces / Replaced by

  • Current replacement option uses 15186 lock with 1/2 inch recessed faceplate, 1/2 inch raised strike, 1-1/4 inch wide Olympus handle, (2) 8 x 1-3/4 inch flat head screws, and (2) 1-3/4 inch pan head screws

Fill out our MPL form or call us to ensure accurate purchasing and correct fit.

Frequently Asked Questions

What is the replacement for the discontinued Great Lakes Window 3-point lock?

The current replacement option uses the 15186 lock with a 1/2 inch recessed faceplate, 1/2 inch raised strike, and 1-1/4 inch wide Olympus handle. Contact our office for installation details as minor modifications are required.

What type of cylinder did the original Great Lakes Window sliding door use?

The original door used a 70mm Italian Euro/Profile cylinder. Solid brass handles were paired with keyed cylinders, while plated brass handles were available with or without keyed cylinders.

What are the rod lengths for this 3-point lock system?

The lower rod is 34-1/2 inches and the upper rod is 47-3/4 inches, both with 1/4 inch diameter.

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Standard Shipping Rates

Shipping applies to the contiguous U.S. (orders to Alaska and Hawaii require a custom quote):

  • $11.95 – USPS Snail Mail (First Class, 10–21 days)
  • $14.95 – USPS Priority Mail (7–10 days)
  • $17.50 – UPS Ground (2–5 business days)

📦 Rates typically cover packages up to 4 lbs. Oversized or heavier items may incur additional charges.

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  • Most orders ship within 2–5 business days of purchase.
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