Sometimes FCC filings are rife with details. T-Mobile and ZTE aren't playing that game right now: a device has shown up at the US agency bearing only the T-Mobile Aspect name and a ZTE F555 model number. That already tells us that it's likely to have 1,700MHz 3G inside, but the rest is left to our imaginings. It could be anything from a humdrum basic feature phone to a hotspot or future smartphone. We're hoping it's something as sleek as the upcoming Athena, but it could be an adaptation of mid-tier devices like the Mimosa X or a Windows Phone like the Orbit. With most details under wraps, we'll have to sit tight until either an official launch or until more details slip. The only certainty is that ZTE isn't finished with the US just yet.