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tension block 
Parts used to control thread tension.
tension disk
Each of the parts between which the thread passes during threading.
tension dial
Button that adjusts the tension based on the type of thread.
eyelet
Hole through which the thread is passed.
tension guide
Part used to direct the thread.
yarn rod
Piece connected to the knitting machine; its function is to support the tension mechanism.
yarn clip
Piece that holds the thread when it is not being used.
yarn tension unit
Piece used to guide the thread toward the tension spring and keep it taut.
tension spring
Spindle that maintains thread tension.
