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GU Upper Latchbolt Extension for Doors Over 8' – 16mm Faceplate, 20-21/32" Length

GU Upper Latchbolt Extension for Doors Over 8' – 16mm Faceplate, 20-21/32" Length

SKU: 6-33479-04-0-SS

$156.16 - $156.16
$156.16
$156.16 - $156.16
$156.16
  • Faceplate Width: 5/8" (16mm)
  • Extension Length: 20-21/32" (525mm)
  • Extension End: Radius, rounded end
  • Finish: Stainless steel
  • Designed for doors over 8' tall
  • Compatible with GU-SECURY Automatic 3-point door locks
  • Tapered latch for reliable strike plate engagement
  • Sold individually
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Before you order, if you'd like confidence this is the right part for your job, please fill out our multipoint lock identifier form or call us at (816) 221-6543 .
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GU Upper Latchbolt Extension – 16mm Faceplate, 20-21/32" (6-33479-04-0-SS)

This GU/Ferco upper latchbolt extension provides an additional locking point for tall doors over 8 feet. Designed for use with GU-SECURY Automatic 3-point door locks, this extension ensures secure engagement at the top of your door.

The extension features a 16mm stainless steel faceplate with a radius (rounded) end for easy installation and a clean, finished appearance. The tapered latch design ensures reliable engagement with the strike plate every time.

Technical Information

  • Faceplate Width: 5/8 inches (16mm)
  • Extension Length: 20-21/32 inches (525mm)
  • Extension End Style: Radius, rounded
  • Material: Stainless steel faceplate
  • Compatibility: GU-SECURY Automatic 3-point door locks
  • Application: Doors taller than 8 feet

Notes

  • Provides additional locking point for enhanced security on tall doors
  • Tapered latch design ensures consistent strike plate engagement

Priced and sold each.

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

Frequently Asked Questions

What door locks is this extension compatible with?

This upper latchbolt extension is designed for use with GU-SECURY Automatic 3-point door locks.

When do I need this extension?

This extension is required for doors taller than 8 feet to provide an additional locking point at the top of the door.

What does the radius end mean?

The radius end refers to the rounded shape of the faceplate, which allows for easier installation and provides a cleaner finished appearance.

At mplocks.com, we strive to provide fast, reliable, and fairly priced shipping. Below you'll find our standard shipping details, important notes, and packing practices.

Standard Shipping Rates

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

  • $11.95 – USPS First Class (5–10 business days)
  • $12.95 – USPS Priority Mail (3–6 business days)
  • $19.50 – UPS Ground (2–5 business days)

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

Processing Times

  • Most orders ship within 2–5 business days of purchase.
  • If your order is delayed, we'll notify you promptly.

Important Notes on Shipping Costs

  • Certain items may have higher shipping costs due to weight or dimensions.
  • We reserve the right to adjust shipping fees. If this applies to your order, we'll contact you for approval before proceeding.
  • If you choose not to accept revised shipping charges, we may cancel your order at our discretion.

Backorders & Billing

  • All credit cards are charged within 72 hours of purchase.
  • This includes orders that contain backordered items.

Our Packing Standards

We take great care to ensure your order arrives safely and securely.

  • Whenever possible, we use recycled paper, cardboard, and eco-friendly packaging materials.
  • Many of our products are purchased in bulk and may not include retail packaging or barcodes. In these cases, items may be repackaged in secure, plain boxes.
  • Hardware ships in retail or contractor-grade packaging when available.
  • Every item is inspected prior to shipping, and additional packing is used if needed.

Quality Guarantee

All items are brand new unless specifically noted. If something is not right, we'll work to make it right—through repair or replacement.

⚠️ Please note: shipping costs are non-refundable.

If you have questions about shipping rates, timelines, or packaging, please contact us before placing your order.

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