The Original Koostik is the result of a year of product evolutionary design and refinement. It is a passive solid wood acoustic amplifier for iPhone, and this now iconic design is in daily use in over 30 countries! By combining two hemispherical sound amplification chambers with carefully designed sound channels, it achieves natural energy free amplification of between 10 and 20 decibels.
This means an increase of 2 to 4 times the volume! Please note that due to it's unique design, the Original does not allow for the connection of your charger while in use with your iPhone. It is a totally "unplugged" amplifier!
Features
● Compatible with all versions of Apple iPhone
● Made by hand in America
● Energy free amplification of 2-4 times the volume of your iPhone's speaker
● Compatible with iPhones without case and iPhones with cases up to 2.5" wide x 0.5" deep