It's Amazon Prime Day, and it's an even bigger event this year.

Amazon has extended Prime Day for four days this year. It was two days last year.

Analysts aren't sure if the extra days will translate to into more purchases with concerns about tariffs.

Adobe Digital Insights predicts that the sales event will drive $23.8 billion in overall online spending

Amazon says it will have deals dropping as often as every five minutes during certain periods.

Some may be eligible for 5% cash back on their purchases for a limited time.

Amazon said it would have special discounts on Alexa-enabled products such as Echo, Fire TV and Fire tablets.

Best Buy, Target and Walmart are also offering deals this week to compete with Amazon.