applied yarns: for folding with cotton, wool, polyester fiber, chemical fiber and blend fabric. fold stock feed spool with different specification to be cylinder rubes witch is used on short fiber twister. features: 1. for any kinds of short and long fiber single merging, the machine has excellent function, stable tension, easy work for next processing. 2. bobbin forming, stable and reliable, applying for any style. 3. use pneumatic technology for yarn package to go up when the tube is full or yarn is break. 4. applied electrical broken end testing and electrical moving-on-length device, the machine could protect the mixture of single and double yarns. 5. yarns pass through straight channel, avoiding the tension changing during merging procedure.