The external charger is very handy with a 6,000 mAh battery and a pair of USB charging ports. One provides a higher, 2.1 Amp current.
I'm not sure such a big phone with a plastic back needs a bumper and another plastic case but Google does include it.
Three sets of earbuds are included for the headphones, which have a built-in microphone. Using the audio splitter, a second person can listen in on tunes or a movie.
It looks fancy but it's just a SIM card for the Project Fi service. Including a paper clip to eject the SIM tray is a nice touch.