It consists of a thin, flexible piezo film that fits between a bridge foot and the top of your instrument, and is carefully and specifically designed so it won't alter the acoustic sound of your bass. Its sound is very natural and woody, with less focus and more body, due to its location on the body of the instrument. There are many different "natural bass sounds", all of which depend on the vantage point; what's your preference? Do you want the sound from one foot away, with more detail and string artifacts? If so, that's not the sound of The Realist. It has less detail - not necessarily a bad thing - due to the location of the transducer in relation to the strings. It provides more of the sound of the instrument "from a distance," where the body sound takes over from that upfront detail, but it is still sensitive to string sounds. Because of the nature of its sound, the Realist is an excellent choice for bowed response - as well as for the classic pizzicato sound. By comparison, pickups with "more detail" can sound scratchy or overly trebly, particularly when bowed.