Xbox 360 gamers are to be treated to an additional peripheral at a later date.

Guitar Hero II screenshot

Joystiq reports that the mystery port found at the base of the X-Plorer guitar for Guitar Hero II on Xbox 360 is in fact designed to take an effects pedal.

The game's instruction manual reveals that the port is clearly labelled the Effects Pedal port, although there's actually no info on what additional wonders this Effects Pedal will enable. The manual merely states "Feature currently unavailable".

We're waiting on an official comment from Activision regarding the mysterious peripheral.