e15 celebrates 25 years of BACKENZAHN™ with a new edition of the iconic side table designed by founder Philipp Mainzer.‎ Introduced as part of the e15 SELECTED collection, a matte-black finish highlights the alchemic process that produces a natural tanic acid reaction in the oak wood, when triggered with a special mixture of natural ingridients.‎ Due to the structural properties of oak wood and its individual degree of inherent acid, the colouring of each BACKENZAHN™ is unique and can vary.‎