Windows 10 will be released July 29 as a free upgrade for Windows 7 and Windows 8.1 users. Those who wish to perform clean installation of the operating system can now pre-order the Windows 10 USB sticks at Amazon.

According to VentureBeat, the Windows 10 USB sticks are available in two variants. The Windows 10 Pro USB Stick available for $199.99 in English and Spanish versions. Owning the USB device will let users install the new system without the need of a Windows 10 DVD.

Even though the Windows 10 release is set for end of this month, the USB sticks that are available from Amazon will start shipping from Aug. 16. Microsoft has conveyed to VentureBeat that retail outlets will start selling the USB drives with Windows 10 after the operating system is officially released.

On Amazon, the seller of the USB sticks is listed as Microsoft. Even though both the Windows 10 USB sticks are not listed on the Microsoft Store or at other retailers such as Best Buy, they are expected to sell them, adds VentureBeat.

According to Digital Trends, Microsoft will be selling Windows 10 in four editions. The retail edition of Windows 10 Home and Windows 10 Professional will be sold for $120 and $200, respectively. OEM versions that are usually bought when a customer builds a new PC will be priced at $100 for Windows 10 Home and $140 for Windows 10 Professional editions.

Owners of legitimate versions of Widows 7 and Windows 8.1 do not need to buy a copy of Windows but simply upgrade to the newer OS for free through Windows Update service. Owners of Windows Vista and Window XP PCs will be required to buy a new copy of Windows 10.

The Redmond-based company is going to announce Windows 10 devices at the IFA 2015 event in September. Some of the speculated Microsoft devices that are expected to get unveiled at are Surface Pro 4 tablet and Lumia 950 and Lumia 950 XL flagship smartphones.