This week, maker of discount Android and Windows smartphones Blu announced two new phones in its "Energy" series: the Studio Energy 2 and Energy X. Both devices come at a low price but promise to offer absolutely huge batteries nonetheless.

Blu, the budget phones you can find at retailers like Wal-Mart and Amazon, doesn't usually stack the specs in their low-cost devices, and that's mostly true about the Blu Studio Energy 2 and Blu Energy X.

Except, according to the company's announcement (via Android Police), these two handsets promise "up to three days of standard usage on a single charge" and an impressive 30 days with a charge on standby.

Studio Energy 2

The Blu Studio Energy 2 comes with a 5,000 mAh battery, the largest of any smartphone on the market, the company boasts. With an aluminum body and a thin 10mm design, the Studio Energy 2 features a 5-inch Gorilla Glass 3 display with 720p resolution, running on a 64-bit quad-core Mediatek processor clocked at 1.3GHz with 1.5GB of RAM.

It features a microSD card slot and 16GB internal storage, 4G LTE connectivity on US GSM networks, an 8-megapixel main camera with a 5-megapixel front facing shooter, and runs Android 5.0 Lollipop out of the box -- all for $179.

Energy X

A new addition to the Blu lineup, the Energy X is only 8mm thick and made with aluminum, packing a 4,000 mAh battery for extra life. It has a 5-inch IPS display (also with Gorilla Glass 3) that Blu only labels as "HD."

Still, there's an 8-megapixel main camera and a front-facing shooter as well, all powered by a 1.3GHz quad-core Mediatek processor with 1GB of RAM. Storage is only 8GB, but the Energy X also comes with a microSD slot for up to 64GB more.

It supports Dual SIM and works on GSM networks with 4G HSPA+ speeds, but no LTE, for just over $100. Oddly, it comes with a little extra bonus over the Studio Energy 2, in that the Energy X runs the less buggy Android 5.1 Lollipop right out of the box.

For budget phones, both devices look pretty nice, especially the Energy X. Their designs seemingly take after the HTC One, with polished aluminum and multiple color options, and both feature surprisingly thin bezels.