Our line of hand-crafted, sustainable, German Design Award-winning smartphone speakers work with any smartphone, are made entirely out of high-quality birchwood, and don't need electricity or special connections. The specially engineered inner sound tunnel and rings increase music volume by 25 dB - a perceived increase of %400. The unique acoustical properties of birchwood deliver a warmer tone, smoother highs, and more prominent bass. Salt Turquoise, Kink Pink, BizViz Blue, and Yolk Yellow. Each speaker comes with a screen-printed cloth package that looks beautiful on display, and hand-signed certificates of authenticity by designer and maker Erbil Sivaslioglu.