VOX AC4TV8 Guitar Amplifier Controls - TONE, VOLUME OUTPUT LEVEL Selector (4W, 1W, 1/10 W) Input/output jacks - Input - External Speaker jack; Output - 4W RMS 16-ohm - Speaker - 1x 8 inch 16-ohm Celestion VX8 custom speaker Valve/tube complement - 1 x 12AX7 (pre) / 1 x EL84 (power) Unit Dimensions - 11.81/300mm (W) x 12.68/322mm (H) x 7.64/194mm (D)