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NATIONAL GUARD Automatic Door Bottom - Automatic Door Bottoms
NATIONAL GUARDAutomatic Door Bottoms

NATIONAL GUARD Automatic Door Bottom

The NATIONAL GUARD Automatic Door Bottom (Single Fin Insert, MPN 420NHMDKB-3) is an aluminum door bottom measuring 36 inches in length and 2 5/16 inches in width, constructed from aluminum. 3G Electric interprets…

SKU 3G-OTH-515138

Also listed as: 420NHMDKB3 · 420NHMDKB 3

Brand
NATIONAL GUARD
Item
Automatic Door Bottom
Part Number
420NHMDKB-3
Category
Automatic Door Bottoms
Available to Order
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Delivery
Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
Payment
Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

NATIONAL GUARD
Manufacturer Part Number
420NHMDKB-3
Type
Aluminum, Aluminum
Lg
36 in
Wd
2 5/16 in

Technical Documents

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NATIONAL GUARD Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The NATIONAL GUARD Automatic Door Bottom (Single Fin Insert, MPN 420NHMDKB-3) is an aluminum door bottom measuring 36 inches in length and 2 5/16 inches in width, constructed from aluminum. 3G Electric interprets customer demand and delivers this genuine industrial product across 14 departments—and far more—with specialist trust anchored in combustion, pumps and controls.

Frequently Asked Questions

What is the NATIONAL GUARD Automatic Door Bottom 420NHMDKB-3 used for?

This automatic door bottom seals the gap under a door to block light, sound, and drafts. It is commonly installed on commercial or industrial doors in facilities requiring fire-rated or acoustic sealing. The single-fin aluminum insert provides a durable, low-maintenance sweep that retracts when the door opens.

What are the specifications of the NATIONAL GUARD 420NHMDKB-3?

The NATIONAL GUARD 420NHMDKB-3 is an aluminum automatic door bottom with a single fin insert. It measures 36 inches in length and 2 5/16 inches in width. The body and insert are both aluminum. The manufacturer part number is 420NHMDKB-3.

Where to buy the NATIONAL GUARD 420NHMDKB-3 worldwide?

3G Electric supplies the NATIONAL GUARD 420NHMDKB-3 automatic door bottom to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for a quote and lead time; we source genuine industrial products across 14 departments and beyond.

How to install the NATIONAL GUARD Automatic Door Bottom 420NHMDKB-3?

Install the NATIONAL GUARD 420NHMDKB-3 by cutting it to exact door width, then screwing it to the bottom of the door using the provided mounting holes. Ensure the fin retracts freely when the door opens. Follow standard door-bottom installation practices for proper alignment and sealing.

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NATIONAL GUARD Products

3G Electric supplies NATIONAL GUARD automatic door bottoms. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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This automatic door bottom seals the gap under a door to block drafts, light, and sound. Made of aluminum, it measures 48 inches in length and 2 1/4 inches in width. Suitable for commercial and industrial door applications requiring a corrosion-resistant seal
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This automatic door bottom seals the gap under a door to block drafts, light, and sound. Made of aluminum, it measures 48 inches in length and 2 1/4 inches in width. Suitable for commercial and industrial door applications requiring a corrosion-resistant seal
This automatic door bottom seals the gap under a door to block drafts, light, and sound. It is commonly installed in commercial and industrial facilities to improve energy efficiency and room privacy. Constructed of aluminum with a single fin insert, it measures 36 inches in length and 1 3/8 inches in width
NATIONAL GUARD
This automatic door bottom seals the gap under a door to block drafts, light, and sound. It is commonly installed in commercial and industrial facilities to improve energy efficiency and room privacy. Constructed of aluminum with a single fin insert, it measures 36 inches in length and 1 3/8 inches in width

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