Teenage Engineering Iss7241B OP-1 Portable Synthesizer - UsedOP 1 is the all in one portable synthesizer, sampler and controller. with additional features like a built in FM radio and an assignable G force sensor for motion controlled effects, there is quite nothing like it. Its modular architecture enables endless sound possibilities without making the workflow complicated or distracting. The compact design and real physical interface makes it inspiring to create music, no matter who you are or how experienced