 Once the guitars have been tuned with an electronic tuner and strummed to ensure that they are in tune, the guitar tech usually sets up the different guitars on guitar racks, ensures that the leather or nylon straps are properly connected, and that the patch cords are plugged in properly.During the show, the guitar tech hands instruments to the guitarist or guitarists according to the types of guitar that are required in the songs that they are playing.For example, a hard rock guitarist may use a "flying-V" guitar for a fast song, and then switch to an acoustic 12-string guitar for a soft ballad.