This is an endpin for a double bass. It has a two-layer structure of iron and carbon. It is a custom-made product by Mitsuke Seiki Kogyo. While retaining the natural tone and sound projection of carbon, the sound has a clearer outline. It is softer than titanium and has a tighter tone than brass. Since there are no grooves, the height of the instrument can be adjusted steplessly. From a tonal perspective, a groove-less design produces a more solid and full sound. Because the inside is carbon and the length is made shorter, it is light in weight. Changing from a long, heavy pin will likely significantly change the perceived weight of the instrument.