Year introduced: 2015
Capacity: 16, 32, 64, 128 GB
Colours: space grey, silver, gold, rose gold
Model number on the back cover: A1634, A1687, A1699
 
Details: the display is 5.5 inches (diagonal). The front is flat with curved edges and is made of glass. The back is anodised aluminium with a laser-etched "S". The Sleep/Wake button is on the right-hand side of the device. The Home button has Touch ID. There's a True Tone LED flash on the back and a SIM tray on the right-hand side that holds a "fourth form factor" (4FF) nano-SIM card. The IMEI is etched on the SIM tray. 
 
See the tech specs for iPhone 6s Plus.