Engadget has spotted a CDMA HTC Windows Phone passing through the FCC with Sprint LTE bands.
The handset is almost 100% sure to be the HTC Tiara, a mid-range Windows Phone 8 handset which is rumoured to be coming to Sprint in Late June or Early July.
The handset will be coming with the next GDR2 version of Windows Phone, which offers some minor improvements, but unfortunately not as much as on a Nokia handset.
According to the FCC the handset (code name PO88100) has NFC, BT 4.0 and WiFi a/b/g/n.
Other specs leaked earlier indicate a 1.2GHz dual-core Snapdragon processor, 4.3-inch Super LCD2 display (WVGA resolution), 1GB of RAM, 8GB of internal storage, 1800mAh battery and an 8-megapixel rear camera (1.6-megapixel front).