With regards to create a new box with easier access, lower maintenance and brighter lighting, the Post Office introduced a prototype run of "Croydon" telephone boxes from 1972, named as such because they were erected in Croydon. The Croydon boxes, which featured a black handset silhouette with bright yellow paintwork, were erected as an experimental prototype to replace the red telephone boxes. However, whilst the trials were successful, the quality of the materials and design made it too expensive for the Post Office to mass-produce and the design was not adopted.