Online retailer Amazon is bringing back Prime Day yet again, a shopping event offering huge deals for Amazon Prime members. 

Here are five things to know about Amazon Prime Day. 

1. It's only for Prime members. 

But you can sign up for a 30-day free trial if you have never been a Prime member or haven't cancelled your membership within 12 months. If you have, you can get a single month of Prime for $12.99. 

2. It's going to be two days this year. 

Prime Day starts at 2:59 a.m. ET on Monday, July 15 and lasts for 48 hours. That's 12 more hours than it was last year. 

3. Amazon is putting over 1 million items on sale for Prime Day. 

There will be over 1 million deals available to Prime members during Prime Day, which is a lot to sort through. Amazon hasn't said much about what will be discounted, but you can count on deals on Amazon Alexa devices, TVs, back-to-school and off-to-college items, clothing and more. 

Last year's Prime Day bestseller in the U.S. was the Instant Pot Pressure Cooker.

4.  Whole Foods will also have some deals.

You can find a special deal at Whole Foods every day from July 10-16. Plus, Prime Members who spend at least $10 at Whole Foods from now until July 16 will get $10 in Amazon credit to use during Prime Day. 

5. Prime Day includes a streaming concert this year, featuring Taylor Swift, Dua Lipa, SZA, Becky G, and host Jane Lynch. 

You watch the Amazon Prime Day Concert live through Prime Video on July 10 at 9 p.m. ET. 

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