High Speed Back-twisting Machine 1,For CAT5E,CAT6,CAT7 2,Motorized take-up with ... Ac motorTension range100g-1000g,stable and adjustableBack-twist tension standVertical double head,tension wheel 120mm,3+3 ditch,pecision potentionmeterPay-off ... -up with constant tansion HR-DB-500/630(bobbin size) High Speed Pair Back-twisting Machine