Erhu Mechanical Nut ☆Please read my profile. ☆Instant purchase OK. This is a mechanical nut for the erhu. It has a pitch adjuster (fine-tuning function). It is easy to attach and detach. You can attach and detach it while the strings are still on. You can easily change the string height just by turning the screw, so you can use it to find the string height that suits you. (With a thread nut, once you've wound it, you have to rewind it to change the string height.) Also, when winding a thread nut, you can use this mechanical nut to fix the string height that suits you, and then wind the thread nut in that state. (This is surprisingly convenient.) I have hardly used it since I bought it new, so I think the condition is good. Shipping will be by regular mail. #Erhu #Nut #MechanicalNut #ChineseInstrument #Huqin #EthnicInstrument