The mobile deals for Amazon Prime Day 2018 keep on coming, and now there are some solid offers on microSD cards available. 

Several SanDisk microSD cards are now on sale at Amazon. That includes the 400GB microSD card, which is one of the larger cards on the market, and it's now hit an all-time low price. If you don't need quite such a large card, Amazon is also discounting the 128GB, 200GB, and 256GB microSD cards.

These SanDisk microSD cards are Class 10 with up to 100MB/s transfer speeds and are A1-rated to load apps faster. They work well in smartphones or tablets, but they also work with other devices, like the Nintendo Switch.

Having a big microSD card in your phone can be super helpful. For example, while many people rely on streaming music nowadays rather than storing a ton of tunes on their phone, cameras are taking higher quality photos and recording 4K video that can quickly eat up a phone's internal storage. Having a big microSD card lets you take lots of photos and videos without worrying about running out of storage.