Elegant letterbox Grundform with a new design and Ruko lock The letterbox Grundform – designed by the Danish architect Bent Ulrik Jensen and the Danish designer Michael Stabell – enchants with its new, breathtaking design. Simple but elegant, made of lacquered steel, stainless steel or copper, this designer letterbox is sure to catch the eye. Grundform comes with a Ruko lock. The Ruko lock is an elaborate security system which securely protects the contents of the letter box against unauthorized access. All the components are made of high-quality materials. As the letterbox has been galvanised, the manufacturer provides a 12 year warranty against corrosion. Grundform can be installed as a wall or standing letterbox. Please order the letter box stands separately (as an accessory).