RIALTO (CBSLA) – With U.S. shoppers putting in tens of millions of orders to Amazon this holiday season, the online retail giant will be working overtime to get packages shipped out.

The Amazon fulfillment center in Rialto, Calif., on Dec. 2, 2019. (CBS2)

This Cyber Monday, Amazon gave CBS2 a behind-the-scenes look of its massive fulfillment center in Rialto.

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Cyber Monday is Amazon’s Super Bowl. Amazon estimates that more than one million packages will be mailed out today alone from its Rialto center. Amazon customers ordered a staggering 180 million items between Thanksgiving and Cyber Monday in 2018.

“Last year [Cyber Monday] was the single biggest shopping day of the year, and this year we expect it to be even bigger,” Amazon spokeswoman Kate Scarpa said.

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The Rialto center employs about 1,000 people working 24/7, along with seasonal help. It’s the hallmark of efficiency, with conveyor belts carrying thousands of items and robots steering racks around the huge warehouse.

There’s a computer which prints out instructions for both the perfect box-size fit for each product and even the exact amount of tape needed for each box.

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U.S. shoppers are expected to spend $9.4 billion on Cyber Monday alone, according to Adobe Analytics.