This machine is passive traction type dual-disc aluminium foil strap release bracket, mainly used for the use of engraving machine and longitudinal covering machine of cables, having the characteristics of simple operation and fast strap change. It uses the tractive force of follow-up equipment to drag the release strap disc to rotate and release the strap, and control the system by using the tension of magnetic powder brake. Make adjustment to the real-time tension when releasing strap by materials to maintain the constant tension.