The MacBook Pro "Core i7" 2.8 15-Inch
(Integrated Graphics/Iris Only/Force Touch - Mid-2015 Retina Display)
technically is a "configure-to-order" configuration of the MacBook Pro "Core i7" 2.2 15-Inch
(Integrated Graphics/Iris Only/Force Touch - Mid-2015 Retina Display),
but also is documented as a separate model for reader convenience.
Other than the processor, these models are identical.

Please also note that this model should not be confused with the also once BTO/CTO MacBook Pro "Core i7" 2.8 15-Inch (Dual Graphics/Force Touch - Mid-2015 Retina Display), which has dual graphics processors.

The MacBook Pro "Core i7" 2.8 15-Inch
(Integrated Graphics/Iris Only/Force Touch - Mid-2015 Retina Display)
features a 22 nm "Haswell/Crystalwell" 2.8 GHz Intel "Core i7" processor (4980HQ),
with four independent processor "cores" on a single silicon chip,
a 6 MB shared level 3 cache,
16 GB of onboard 1600 MHz DDR3L SDRAM,
512 GB of PCIe-based flash storage, and
an integrated Intel Iris 5200 Pro graphics processor
with 128 MB of "Crystalwell" embedded DRAM (and shared system memory).

It also has an integrated 720p FaceTime HD webcam and
a high-resolution LED-backlit 15.4" widescreen 2880x1800 (220 ppi) "Retina" display
in a case that weighs just less than 4.5 pounds (2.04 kg).

It does not have an internal optical drive.

Connectivity includes
802.11ac Wi-Fi,
Bluetooth 4.0,
two USB 3.0 ports,
two "Thunderbolt 2" ports,
an HDMI port,
an audio in/out port, and
an SDXC card slot.

In addition, this model has a backlit keyboard, a new advanced "Force Touch" trackpad, a "MagSafe 2" power adapter, and an internal, sealed battery.

Compared to its predecessor, this model practically is identical, but it has faster flash storage, a higher capacity battery, and a more advanced "Force Touch" trackpad. It has some different identifiers, too.

Please note that stock images are used