The Seattle-based ecommerce giant is encouraged by the strong sales it saw on Thanksgiving and Black Friday, said Doug Herrington, Amazon’s senior vice president for North American retail, in an interview with Fortune on Monday.

Though Amazon won’t disclose actual sales figures, it’s said to have generated about 36% of all online sales during last year’s Cyber Monday.

Cyber Monday sales as a whole are expected to hit a record $3.36 billion this year, up more than 9% from last year.

Related: Here Are the Best Apple Cyber Monday Deals

Some of the top-selling products on Amazon.com include e-readers, TVs, and toys, says Herrington. And more and more of those purchases are being made on a smartphone. Last holiday season, more than 70% of Amazon’s customers shopped using a mobile device. That number is expected to climb.

Inside Amazon’s massive New Jersey fulfillment center, the energy is electric. The facility is the size of 28 football fields and houses more than 4,000 employees who package and ship the millions of products ordered during Cyber Monday. Amazon has hired more than 120,000 seasonal employees nationwide just to keep up with demand on its busiest time of year.

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And what happens when the 2016 holiday season is over? The hustle at the fulfilment center never ends, Herrington says. “Right after this holiday finishes, we start getting ready for the next one. It’s a big process. It takes all year.”