Comcast officially unveiled its mobile offering back in April, and now has begun taking sign-ups at its Xfinity Mobile wireless site for customers who have its high-speed internet service. The company will depend heavily on its 16 million WiFi hotspots supplemented by coverage from Verizon Wireless, which Comcast entered into an MVNO with several years back.

Data options include an unlimited choice for $65 per line on up to five lines with no usage limits, or $45 per line for subscribers with premium X1 packages. According to the company’s website, all customers can get the $45/line price through July 31 during a launch promotion. While there are no monthly data usage limits, speeds are reduced after 20 GB of cellular data usage to a maximum of 1.5 Mbps download/750 Kbps upload.

Subscribers are also being offered a per-gigabit choice that goes for $12 per GB of cellular data across all lines on an account each month. They can switch between data options at no cost.

In terms of phone options, there is no bring your own device (BYOD) choice. The company is offering a selection of newer iPhones and Android devices from Samsung and LG.

If customers want to cancel their Xfinity Internet service, they can continue their mobile service but will incur an extra fee, according to Xfinity Mobile’s FAQs. With the “By the Gig” option, each line would see a $10 monthly line access fee in addition to the $12/GB paid for data. Customers on the “Unlimited” plan who cancel their internet service would also have a $10 monthly line access fee added to their regular per-line monthly charge.