Roland Micro Cube Battery Powered Guitar Amplifier | M-CUBE-GX with 8 DSP Effects, 8 COSM Amplifier Models, Chromatic Tuner, iOS i-Cube Link (Black) Ultra-compact guitar amp with custom-designed speaker (Best with Polaroid AA Batteries) Eight COSM amp tones, including the ultra-heavy EXTREME amp Eight DSP effects, including HEAVY OCTAVE and dedicated DELAY/REVERB with spring emulation i-CUBE LINK jack provides simple audio interfacing with Apples iPhone, iPad, and iPod touch (interface cable included) MEMORY function for saving favorite amp and effects settings