The material is fishing line to be used "huroroka-bon" referred to as the worth (worth) strings. Stretch feature a moisture resistant, resistant to temperature changes. "The good sound of more nuke", if your preference is highly recommend. This item features a thinner and lighter, with sound. The color is clear. kuriahuroroka-bon·raitoge-zi is brown, with a more delicate and transparent so you can aim the sound production compared with it.