Features:Eco-friendly heat shrinkable tube does not produce toxic and harmful substances.These heat shrink tubes are made of high quality PE which is flame retardant, soft and shrink fast.Different colors of heat shrink tubes are great for wire identification, concise and clear.There are total 670pcs heat shrink tubes can meet you basic daily needs. It is widely used in wire connection, great for garages, auto electricians, mechanics, workshops etc.