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WD40PURX 4TB Surveillance Class Hard Drive from WD
WD Purple WD40PURX 4TB Surveillance 3.5" Internal SATA Hard Drive
Western Digital Purple 4TB,Internal,5400 RPM,3.5 inch (WD40PURX) Hard Drive for sale online | eBay
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WD Purple 4TB Surveillance Hard Disk Drive 3.5" - Newegg.com