The Holy Grail Nano is a compact digital reverb pedal that features a classic Spring reverb emulation, smooth hall reverb and a special ‘Flerb’ effect, which combines flanging with spatial reverb for a unique ethereal sound. The Electro Harmonix Holy Grail Nano guitar effects pedal comes with a power supply and also features a true bypass mode. True bypass Simply the finest "spring" reverb available Smooth "hall" reverb tailored to the guitar Flerb combines flanging with spatial reverb for a unique ethereal sound. 96DC-200BI power supply included.