Swaytronic Heat Shrink Tubing White/Black. Application: The Swaytronic heat shrink tubing with a shrink ratio of 2:1 is a high-quality all-rounder. It is resistant to alcohol and acids and is made from high-quality PVC. The film serves to protect and insulate rechargeable batteries and electronic components. Customer Benefits: Want to know which shrink fits your battery best? No problem. You can determine the suitable shrink directly with the following formula: (Width of the battery in mm) + (Height of the battery in mm) x 1.05 = required width of the shrink in mm. Shrink temperature: 130 - 160 degrees. Shrink ratio: 2:1. Shrinkage rate: 46%-52% (horizontal), 10%-20% (vertical). Unit: Available per running meter.