IMPORTANT UPDATE: Microsoft no longer allows upgrade from Windows 7 to Windows 10 with the same Activation Key so please disregard the information below about how it's possible to Activate Windows 10 with the Activation Key of Windows 7. You will need to purchase a Windows Activation Key from Microsoft if you are upgrading from Windows 7. 128 GB, 256 GB, 512 GB or 1 TB (Choose Above) SSD SATA Hard Drive Laptop with Windows 10 Pro Installed Legacy 64-bit IMPORTANT NOTE: Windows 10 PRO was installed on this Hard Drive in Legacy Mode. If your System has both UEFI and Legacy Mode, then make sure Boot Mode is set to Legacy mode otherwise your system will not detect the Operating System on this Hard Drive. PLEASE READ BELOW BEFORE MAKING A PURCHASE ACTIVATION: This is a genuine version of Windows - not a pirated 'pre-activated' one. Activation therefore may be required.- If your computer came with Windows 10 PRO pre-installed, then you don't need to do anything. Windows will automatically detect your system's digital license (which is embedded in the hardware) and activate. Your system will also detect the Digital License Key and activate Windows if your computer came with Windows 8 Pro. If your computer came with Windows 7 PRO, then you will need to purchase a Windows 10 PRO Activation Key from Microsoft as Microsoft no longer allows Activation of Windows 10 PRO with a Windows 7 PRO Activation Key. Activation/Product key does not come with this SSD, and you may need to buy one if none of the above mentioned scenario to your situation. Compatible with 99% of Laptop and Desktop brands. SSD comes with 3 years manufacturer Warranty. Details on back of packaging. You are buying a SSD, with pre-installed Windows. This is ideal for new computer builds or to replace a dead or dying drive in an existing computer. No technical knowledge is required. Simply install drive in Laptop, Power it on, let it automatically update devices for your hardware, and you're good to go! This drive is suitable for any laptop model, that has a SATA connection pretty much any from the past 10-12 years. If you want to install this SSD in to a desktop computer, you will need to buy a 3.5" Adapter caddy. Returns: As with all our items we have a 60 day return policy. Item must be in original condition for a full refund. Depending on the item condition upon return, we reserve the right to decide whether to issue a full or partial refund. Shipping: Shipping is via USPS 1st Class Mail or Priority depending on Order Size. While may show you an estimated delivery date, this is not guaranteed as USPS has no guaranteed delivery times for 1st Class Mail. We will ship within 1 business day of purchase, after that we have no control over delivery. If you need your hard drive faster, then choose the Priority mail option. USPS Priority Mail which has 2-3 day delivery times depending how far you are from CA.