PREMIUM MATERIAL:Spade Connectors are made of high quality copper. The dual wall of heat shrink tubing is adhesive lining. SAFETY ASSURANCE:The Heat Shrink Spade Connectors crimp, shrink, and seal well, which make your connection much safer and more reliable. WIDE APPLICATIONS:Spade Terminlas can be widely used in household electrical wire connections, automotive & marine boat repairs. PACKAGE CONTENT:100 PCS Female Electrical Quick Disconnect Wire Connectors. TIPS:In order to make the best result, better use a hot gun to reduce the size of the shrink tubings of Spade Terminlas, until the terminals are filled with the adhesives.