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Overview

4 TB NAS-optimized internal HDD with SATA 6 Gb/s interface, 5400 RPM, and 256 MB cache — designed for reliable 24/7 storage in small to medium NAS systems.

WD Red NAS 4TB HDD – 3.5″ SATA NAS Hard Drive

Model: WD40EFAX
Web Code: 19660772
Sold and shipped by | 1.9 seller rating (13 reviews)

Available for deliveryAvailable online only

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Warranty

Check with the manufacturer for details.

For Quebec residents: See the Availability Guarantee disclosure in the Specifications section below.

Built for NAS systems (up to 8 bays) and designed for reliable 24/7 continuous operation.

4 TB storage capacity provides ample space for backups, media libraries, and shared network data.

SATA 6 Gb/s interface ensures fast data transfer speeds and wide system compatibility.

5400 RPM performance class offers a balance of quiet operation, low power consumption, and steady performance.

256 MB cache helps improve data flow and supports smooth multitasking workloads.

NASware firmware enhances drive compatibility, reliability, and performance in NAS environments.

Supports a workload rate of up to 180 TB per year, suitable for home and small office NAS use.

Built with Native Command Queuing (NCQ) and advanced format technology for efficient data handling.

Low vibration and heat design ensures stable operation in multi-drive NAS enclosures.

RoHS compliant and engineered for energy-efficient, environmentally responsible use.

Backed by a 3-year manufacturer warranty for long-term peace of mind.

Product Condition
Brand New

For Quebec residents – Disclosure under the Consumer Protection Act

In compliance with Bill 29, Best Buy and third-party sellers on Best Buy Marketplace do not guarantee the availability of replacement parts, repair services, or maintenance information for any products. Coverage provided through any Best Buy Protection programs and applicable manufacturer warranties, if any, remain in place. Please contact the manufacturer directly for information about their availability guarantee.

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Processing Time

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Shipping Area Restrictions

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  • Quebec
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