Use for cover the bare wire part with these tubes, heating with heat gun or even hair dryer (hot enough), the tube will shrink and protect the wires with excellent electric insulation performance. Assorted collection of heat shrink tubing, 11 size in 6 colors. Retraction ratio: 2:1, Operating Temperature: -55C to + 125C, flame retardant. Internal diameter: 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 5mm, 6mm, 8mm, 10mm Assorted in a transparent plastic case for easy carry and better organization. Color:Black, Red, Blue, Yellow, Green, Transparent Packing List: 80pcs x 1.0 x 38mm approx. Black 80pcs x 1.5 x 38mm approx. Yellow 50pcs x 2.0 x 38mm approx. Blue 50pcs x 2.0 x 38mm approx. Black 30pcs x 2.5 x 38mm approx. Black 30pcs x 3.0 x 38mm approx. Green 30pcs x 3.0 x 38mm approx. Transparent 30pcs x 3.5 x 38mm approx. Black 40pcs x 4.0 x 45mm approx. Black 30pcs x 4.0 x 45mm approx. Red 30pcs x 5.0 x 45mm approx. Black 20pcs x 6.0 x 45mm approx. Yellow 20pcs x 8.0 x 45mm approx. Red 20pcs x 10.0 x 45mm approx. Blue 20pcs x 10.0 x 45mm approx. Black 20pcs x 10.0 x 45mm approx. Transparent Spec: Minimum Shrinkage Temp: +84 Full Shrinkage Temp: +125 maximum Operating Temperature: -55 to + 125 Dielectric strength: 15 kV / mm Flammability: Flame Retardant Cutting method: Scissors or sharp knife Product size: 15.5*13.3*3.7 cm Weight: 185g/bag Package includes: 1bag*heat shrink tube