http://www.ikmultimedia.com/irigstomp/features/
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Features:
Compact, durable yet lightweight, aluminum-cast enclosure integrates easily into any traditional pedalboard.
Can be used inline with other effects pedals, or directly connected to amplifiers or PA systems using regular 1/4" guitar cables, with no need for adapters.
Allows precise adjustment of the signal for perfect guitar and bass levels with its large input gain knob.
Active battery-powered output circuit improves headroom, especially when used with high-gain amplifiers in the AmpliTube app, reducing feedback and crosstalk when recording.
The bypass switch allows engaging or bypassing the AmpliTube app chain of effects – like a traditional stompbox – for seamless integration into any existing rig.
Ultra-compact form-factor can be easily carried on the road.
Features a 3.5mm/1/8" jack for silent practicing with headphones.
Includes AmpliTube FREE app and can be used with any other guitar processing app that uses the iOS mini-jack
Has an ultra-small, compact profile that can be carried anywhere with ease.
Compatible with iPhone/iPod touch/iPad.