The Valeton GP-1 is a compact, high-performance guitar multi-effects processor that offers a potent effects processing platform and complete feature set. It allows you to improve your skill and experiment with different guitar effects, all with one simple-to-use, portable device. The GP-1 has 100 effects to choose from and allows you to run 8 effects simultaneously. It also provides an EXP jack that allows you to connect an external Expression Pedal, which can be assigned to the effect you want to control for real-time effect changes.