https://www.techradar.com/news/buy-an-htc-vive-pro-at-amazon-and-get-dollar100-worth-of-gift-cards

Just for Amazon Prime Day 2018, the HTC Vive Pro is getting a little promotion of its own on the mega online retail site. 

If you have a Prime membership and you purchase an HTC Vive Pro at Amazon, you'll also get a $50 Amazon gift card and $50 Viveport gift card along with the headset.