We recommend having this product installed at a workshop as it requires completely loosening the instrument to replace it. Please note that we do not provide guidance or instructions for personal installation. This is a tail cord made primarily of polyethylene fiber. It can be used for both violins and violas. It has a tensile strength of approximately 300kg, which is stronger than the nylon and stainless steel wires currently in common use. It is also quite resistant to abrasion, so you can use it with confidence. It is characterized by a good response and a sound with volume and softness. However, due to the characteristics of the product, the sound will be quite dull for the first 1-2 days after installation, so please evaluate its performance after 24 hours or more (72 hours is recommended). We recommend using a double fisherman's knot for tying the tail cord. Also, there are many types of commercially available polyethylene cords, and some of them, even if thicker than the ones we sell, may not have the necessary strength as a tailgut due to their mixing ratio. Please be careful if you are purchasing products for purposes other than their intended use. #Nakajima Stringed Instruments Workshop