The Businessline NBD is a lightweight binaural neck holder headset. The innovation of wearing it around the neck is especially developed for the professional use in call centres. The outstanding characteristic of the Businessline NB series is the connection to the earlap, called Open-Ear-Gain Technology, well known in the industry of hearing aids. This technology avoids covering the earlap by an earpiece or an ear olive. Acoustic signals are conducted through a silicon tube to the edge of the ear. There, the natural amplifying task of the earlap assists to amplify the sound in an inartificial, natural way. Thus, an optimum ratio between signal and noise is achieved. Headsets of the Businessline-series are equipped with a noise cancelling (NC) microphone. However, an omni-directional microphone can be ordered upon request instead. The Businessline NBS offers Acoustic-Shock-Protection (ASP) to shield the ears from increased noise levels. A raised edge, located on the top side of the microphone marks its position and allows both, accurate direction and optimum noise compensation.