Back in March, Amazon announced AmazonFresh Pickup, a grocery service that lets Prime members drive to a pickup location so their online orders can be loaded straight into their vehicle. Now, Wallmart is testing a similar concept in Oklahoma City that uses a huge, automated kiosk.

The feature, available at the Walmart Super Center at N Council and W Britton Roads, is similar to Amazon’s in several ways. Users place grocery orders either online or through a mobile app before driving to the pickup point for collection.

But unlike AmazonFresh Pickup, employees pack the items into bags ready for the customers to collect themselves. After arriving at the 24-hour kiosk, it’s simply a matter of typing a five-digit code into the machine, which will then retrieve the goods. The 20-foot-by-80-foot building contains refrigerators and freezers that keep the groceries fresh.

Using the service is free, but there is a $30 minimum order limit, so it’s not ideal if you’re only looking to purchase a small number of items. AmazonFresh Pickup requires a Prime membership, but there are no minimum order requirements.

Amazon is trying to compete with Wallmart in several areas of the grocery market. Jeff Bezos’s company is still experimenting with its cashier-less convenience store after the public launch was delayed due to technical issues.

Wallmart says it’s been testing grocery pickups since 2014 and offers the service in more than 600 stores across the US. A similar kiosk concept is already used in the UK by supermarket retailer ASDA, which is owned by Walmart.

Walmart is also testing another way for customers to retrieve their online orders: giant, vending machine-style pickup towers. They’re currently being used in Atlanta, Bentonville, Detroit, Houston, and Raleigh, and are designed to make collecting non-food orders quicker and easier.