This particular iPhone 6 model was used an AT&T network (and functioned throughout North America). All iPhone 6 models had a 4.7-inch multi-touch screen at 1334×750 (326 ppi, Retina HD display). It had two cameras: a rear 8 megapixel iSight camera (1080p) and a front 1.2 megapixel FaceTime camera (720p).
The iPhone 6 was originally available in three color options: silver (white glass front and a silver aluminum back), gold (white glass front and a gold aluminum back), and space gray (black glass front and a medium-gray aluminum back). The iPhone used a unibody design with rounded sides (similar to the iPod touch Generation 5). The glass screen curved slightly at the edges. It also included a Touch ID fingerprint sensor.
The iPhone 6 used a 1.4 GHz 64-bit Apple A8 processor with 1 GB of RAM and 16, 32, 64, or 128 GB of storage. In addition to 802.11a/b/g/n/ac Wi-Fi, Bluetooth 4.0/4.2, and LTE (4G), it included NFC for Apple Pay transactions. It had both a bottom-mounted headphone jack and a Lightning port.
Source: EveryMac.com