Boss (Roland) ACA 230 G power supply 9V DC, 150mA, not constant voltage circuit, polarity minus inside, connector dimensions inside 2,5mm, outside 5,5mm, for A-30, A-33, A-37, AX-1, AX-7, BF-1, CS-3, MA-1, PC-160, PC-160A, PC-180, PC-200, PC-200MKII, PD-1, PK-5, PV-1, PW-1, RC-3