The Volta Sound Block is a passive sound amplifier for your iPhone. Passive amplification means no electronics, no chargers, no blue-tooth gadgetry to mess around with. Just a solid block of Northwest Alder from our backyard here in Oregon, and a Bison horn, allowing us to draw the maximum volume from your iPhone speaker. The Sound Block attaches to the Horn using Neodymium Magnets, which allow for maximum holding power, easy horn adjustment, and easy transportation. To top it off we line each Block with wool from Pendleton Woolen Mills to keep your precious iPhone scratch-free. Each Sound Horn is delivered to you in it’s own hand printed travel bag.