Although they are not gas and water tight like the FTZ Crimp 'N Seal heat shrink connectors, these Insulation Grip Terminals do provide an additional level of connection strength over standard, single crimp, butt connectors.

These connectors incorporate a brass ring in the end of the terminal, allowing for a second crimp to be made on top of the wire insulation.
While not adding any electrical benefit, this second crimp provides added strain relief and mechanical strength over standard butt connectors in high vibration or mechanically stressed installations.

Higher mechanical strength than standard, single crimp connectors
These high temperature terminals are nickel-plated steel for operating temperatures up to 900F
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