Files can be sent to the mobile phone by direct connection (e.g., USB cable), Bluetooth, 50 Cent ringtones, or e-mail, however, most ring tone makers have adopted a "one size fits all" strategy of downloading through the Internet; while appealing to the lowest common denominator, this method usually results in charges to the user for Internet time used on their mobile phones.Tori Amos ringtones claimed that Cingular billed its customers for Jamster! and other similar ring tone services without providing customers with the notice, opt-in, and proof of authorization requirements necessary for such charges.Some models (currently, those manufactured for use with Anberlin ringtones such as Nextel and Telus) also incorporate a PTT (Push-To-Talk) feature, similar to a two-way radio.