Moto Z devices can be paired with magnetic back covers that snap into place to expand the handsets' functionality, and the company promotes its own modules while allowing third party manufacturers to create their own. Mophie counts among the third-party brands to hop on board with Motorola's vision, and Verizon – being one of the US carriers to offer the Moto Z series in the country under the "Droid" sub-brand – has now started offering the Mophie Battery Mod on pre-order terms for the price of $79.99. As the name suggests, the Mophie Battery Mod is a so-called "juice pack" or battery bank designed to breathe more life into compatible Motorola smartphones.