JBass is a four strings American Fender Custom shop Jazz bass with flatwound strings.
The first Jazz Bass was made in 1960. With longer and narrower necks than previous Fender models this new design was intended to mimic the feel of a stand-up bass.
Back then, even the guitars were made with jazz musicians in mind, for instance, the new mid tones that they could now produce.
The sound of the Fender Jazz Bass guitar has been crucial in the development of signature sounds in certain musical genres, such as funk, disco, reggae, blues, heavy metal and jazz fusion and is now used a wide variety of genres.