This heat shrink connector kit can be used in different wiring projects. The heat shrink butt wire connectors have and could be applied in wet environment like boat or in your daily life. You can use them for home application as well as science projects. Features - ColorAssorted Color - Material: Plastic and tin ring. - Size: about 4.00X3.70X4.00cm/1.57X1.45X1.57in. - Solder seal connection perfect fit in every application. - The color codes of these heat shrink tubes enables easy selection for the correct application. - Polyolfin tube shrinks with heat and provides sealed structure to protect the wire inside. - Due to high waterproof, these tubes are commonly preferred in automotive sector as well sector. - Solder seal wire connectors can also be used in the house, and school. Package list: White Solder Heat Shrink Sleeve 70 x Red Solder Heat Shrink Sleeve 60 x Blue Solder Heat Shrink Sleeve 20 x Yellow Solder Heat Shrink Sleeve 600 x Black Heat Shrink Sleeve