3M™ Seamless Butt Heat Shrink Connector, 43809, 63-SH, withstands a maximum temperature of 221 degrees f (105 degrees c). 3M™ Scotchlok™ Heat Shrink Butt Connector ensures an ideal fit with great performance. It withstands a maximum temperature of 221 degrees F (105 degrees C). Electrolytic copper construction offers good conductivity and a tin-plated finish resists corrosion.