Frazzled parents in six new cities will now be able to order baby formula in the morning and have it show up on their doorstep by the afternoon.

Amazon AMZN is expanding its same-day delivery service to six new metro areas: Baltimore, Dallas, Indianapolis, New York City, Philadelphia and Washington, D.C. The metro areas of Los Angeles, Phoenix, San Francisco and Seattle already have the service.

Amazon Prime members can get unlimited, same-day deliveries for a one-time fee of $5.99. Non-prime customers pay a first-time fee of $9.98 plus 99 cents for every subsequent item.

Packages that can be delivered on the same day include books, movies, video games, back-to-school items and common household goods, such as shampoo, or baby wipes. Orders must be placed by noon in order to receive delivery that day. There are also additional items that can be ordered for next-day delivery.

The move is part of Amazon’s drive to deliver its products to customers as quickly as possible.

In July, the online retail giant asked regulators to allow it to use drones as part of its plan to swiftly deliver packages to customers.

The online retail giant sent a letter to the Federal Aviation Administration asking it to ease its restrictions on drone-testing in the U.S. in order to allow Amazon to experiment with its unmanned aircraft outdoors near the company’s Seattle headquarters instead of one of the six FAA-approved sites elsewhere in the country.

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