Boss GT-8 Multi-Effects Guitar Pedal w/Power Supply - UsedOwn every Boss effect with one pedal! The GT 8 guitar effects processor features 200 preset options, and you can use up to 13 effects at once and put them in any order. The GT 8 features the dual COSM amp models, letting you switch between two different amp sounds, plus a solo boost function. It has its own expression pedal. You can also insert other pedals through the GT 8 effects loop. The effects unit shows signs of wear. There is a missing knob