On Friday, you can get a Prime subscription for $79.
Amazon Prime
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This article originally appeared on Money

If you've been thinking about signing up for Amazon's popular Prime service, Friday might be your chance to strike.

On Friday, Amazon will offer a 20% discount for Prime, cutting the price from $99 a year to $79 for new members, Business Insider reported. The sale will last just a little longer than 24 hours, from 12 a.m. ET to 11:59 p.m. PT.

Prime members receive a number of perks, including free two-day shipping, photo storage through Prime Photos, and access to Prime Music's library of more than two million songs. Your Prime subscription will also give you access to Prime Video, which features thousands of movies and TV shows, including original Amazon series like Transparent,Mozart in the Jungle, and Good Girls Revolt.

Prime has been a big win for Amazon: At the end of 2015, subscriptions of the service had spiked by 43% from the previous year, and studies have shown that Prime members' annual spending on Amazon more than doubles that of customers who don't belong to the service. Even better news for the online retailer: A report published this spring found that 70% of American households earning more than $112,000 are Prime subscribers — meaning that the company has carved out a sizable niche among customers with disposable income.