These are the so-called newcomers from the company's Wireless N Router series.
The older ones are getting 4G support too. Called The Portable Battery-Powered Wireless N Router (TL-MR3040) and Wireless N Routers for home networks (TL-MR3220 and TL-MR3420), they have only supported 3G and/or 3.75G networks before.
The networks of Verizon, AT&T and T-Mobile are all compatible with the devices.
DSL and cable network connections are still preferable of course, being faster and more stable. 4G can be a good backup when they crash though, for whatever reason.
"The existing inventory of 3G/3.75G Wireless N Routers is being phased out and the 3G/4G products will be in retail channels beginning November 2012," said Lewis Wu, the director of sales at TP-LINK USA.