2-1 Ratio - shrink to 1/2 of its original diameter and makes a tight seal, diameter 3/16 (0.2 inch) (5 mm), 80 feet long, please see diameter chart(picture 3). Safe & ECO-Friendly - UL Listed for up to 600 voltage -55-125℃ working tempurature which ensures its safe and reliable, RECH/ROHS compliance halogen and lead free protect you and your family. Good Tightness - Our 2/1 heat shrink tubing has the advantages of good electrical insulation, good tightness and corrosion resistance, VW-1 Flame Retardants, High temperature resistance shrinkable wire. EASY TO USE - Choose the right size you need and simply slide shrinking tubes over your connection point and apply heat around 70-125℃ temperature evenly with a hot air gun. APPLICATIONS - Shrink tube are mainly used for industrial repair, ship, automotive, wire links, anti-rust and anti-corrosion protection of solder joints, and audio and electrical DIY. Wire ends, harnesses, electronics protection and insulation treatment, fitness equipment parts and steel structure surface protection and so on.