The HTC One just made its first official appearance (unless you count its brief showing by Peter Chou at the year-end party as "official") on Tuesday, and while we haven't been given any specific availability in the US, its models are at least starting to receive approval from the FCC. This particular model sports Sprint-specific LTE (band 25) and also includes 802.11ac support, a telltale sign that this is indeed the Now Network's One. The fact that the docs detail the test unit as a production model is a solid indication that HTC's flagship is well on its way to Overland Park, and soon. And it doesn't appear to be alone, either; two other variants snuck through the process of federal approval, one with quad-band LTE (bands 2, 4, 5 and 17) and another with dual-band (bands 4 and 17). It seems that HTC isn't wasting any time on bringing its attack to US shores.