100pcs Insulated Heat Shrink Waterproof Butt Connectors Wire electrical 22-10GA 100% brand new and high quality Standard crimp and then seal heat shrink butt connectors polyolefin tubing in outside hot melt adhesive in inside The translucent heat shrink material allows for visual inspection of the connection, and has the wire gauge printed on it. When properly heated and shrunk they provide a seal that is resistant to water, steam, salt and other contaminants. For marine, automotive, outdoor, or harsh environment use.