MECCANIXITY Battery Wrap PVC Heat Shrink Tubing 150mm Flat 10 Feet Light Green Good Insulation for Battery Pack: Amazon.com: Industrial & Scientific
50x75mm PVC Tube Insulation Film With Heat Shrink Wrap, Re Wrapping Film, And Sealing Sleeves Includes 2*18650 3.7 V Rechargeable Battery From Cheapezy, $0.08 | DHgate.Com