These were Bang & Olufsen’s first headphones and were of the semi-open type which allowed some intrusion of background noise so one was not completely oblivious to the outside world. They were described as being orthodynamic in principle which essentially meant they used a single point to drive a membrane. In other words they had a standard coil driven speaker as opposed to an electrostatic plate. Nonetheless, the headphones looked sleek and were comfortable to wear. The pads were covered with a type of leatherette which disintegrated with age though this had no effect on sound quality. They were presented in later years in a rather splendid box with a drawing clearly inspired by Leonardo da Vinci but featuring the U 70! These were a popular addition to the range and were the most substantial of all B&O headphones.

The U 70 was fitted with a long cable and a ¼" stereo jack plug. They could be used with most of the audio products of there period, for both private listening with Beomasters and Beocenters, and for monitoring purposes with some Beocord models. They could also be used with the new 33XX Beovision TV sets which appeared a year of so later. The U 70 was replaced by the Form 1.