Martin Rowlands developed the TRIM phone in the 1960s, for the General Post Office (GPO) in England. It was meant to be a fashionable alternative to existing models. The handset rested vertically across the base, the buttons lit up when dialled and, a new electronic ringer replaced the traditional bell. In fact, this is what the acronym TRIM implied: Tone Ringer Illuminated Model.

(The displayed piece is a replica of the original and uses modern push buttons instead of the original rotary system.)