Amex Platinum Card Streaming Subscription credit triggers for individual Kindle book purchases

I really appreciate Amex going out of their way to offer additional perks credits to offset the high annual fees on a travel card. The new $20/mo Streaming subscription credit is a perfect fit for the situation. Kindle Unlimited subscription is on the Amex Streaming list but it doesn’t mention individual books

• Discount: Amex is offering a $20 monthly credit for specific US streaming subscriptions. It seems to be working for digital purchases at these services
• Payment: Amex Personal Platinum Card, Amazon Digital Slow Shipping Credit

Estimated Total: $1.99 – 1.50 (Amazon Digital Credit) – $0.49 (Amex Streaming Credit) = Free after credits

Do test buys before a major purchase

Amazon Digital Shipping Credit can be used for all kinds of digital products