O2 has launched a new mobile broadband bolt-on which allows subscribers unlimited internet access for a set fee.

The Web Bolt On will be available to Pay & Go customers and to clients on Pay Monthly contracts, who will be permitted to browse the internet using their mobile phones as much as they like for a charge of £7.50 per month.

O2 is also due to launch two further data packs next week: the 02 Web Max is priced £30 per month for unlimited access and enables customers to connect their handset to a PC or used a data card.

Meanwhile, a new deal for customers with BlackBerries, dubbed BlackBerry Unlimited, offers unlimited access for £10 per month as well as the facility to access e-mails via their handsets.

All three offers are, however, subject to fair usage caveats of 3GB for the Web Max and 200MB for the Web Bolt On and Unlimited Blackberry deals.

Sally Cowdry, director of marketing at O2, said: "O2 has a whole range of devices which provide a great mobile internet experience such as the Xda Orbit, BlackBerry and, of course, the Apple iPhone - and now we are offering unlimited Bolt Ons to help our customers do what they want without worrying about the bill."