Blue + White Color Coding for Identification. Made of premium insulation materials-PVC for any car, automotive, audio, or low voltage applicationBlue B connector is waterproof for outdoor use. and white B connector is dry for indoor use.Easy "Funnel-entry" design, No need to strip wires, Save time and money . Solid dependable splice in wires ranging from 18 to 30 gauge.Non-hardening gel moisture barrier, rugged protective outer covering and are filled with a corrosion resistant silicone gel.