The different colors of electrical wire nuts (also called twist-on wire connectors) indicate the size and capacity of the connector, meaning the number and gauge of wires they can securely connect. Each color typically corresponds to a specific range of wire sizes and combinations. Here’s a general guide:

Common Wire Nut Colors and Their Usage:

Gray

• Typically used for very small wire connections.
• Works with 22 to 16 gauge (AWG) wires, ideal for low-voltage wiring.

Blue:

• Used for small connections, often for light-duty applications.
• Suitable for 22 to 14 gauge wires.

Orange:

• One of the most common for residential wiring.
• Can handle 18 to 14 gauge wires, depending on the number of wires.
• Frequently used for light fixtures and switches

Yellow:

• A versatile size, often used for residential and commercial electrical work.
• Typically used with 18 to 12 gauge wires.
• Commonly used in outlets and light fixtures.

Red:

• Larger connectors designed for bigger combinations of wires.
• Suitable for 18 to 10 gauge wires.
• Often used for connecting multiple circuits or heavier wiring applications like appliances.

Tan:

• Often similar in size to yellow connectors but can handle more wires.
• Typically works with 18 to 12 gauge wires, often used in place of yellow ones.

Green:

• Specifically designed for grounding wires.
• Used for 14 to 10 gauge ground wires, often found in grounding electrical systems

Black:

• The largest size connectors, meant for heavy-duty applications.
• Works with 10 to 6 gauge wires, frequently used for high-power devices like ovens or air conditioning units.

These electrical wire connector nuts allow for simple and efficient connections of multiple wires with varying sizes. CableTiesAndMore now carries two varieties of wire connectors, non-winged fixed spring and winged free spring. To use, simply remove the insulation from the wires near the connection end. Next, twist the wires together, though this isn't required if you're using the winged, free spring connectors. Then screw on the connector over the ends of the exposed wires. We provide an array of different sized connectors to meet your wiring needs. Our products are color-coded to aid in identifying the gauge of wire that it will effectively accept.

A cone shaped, plated steel spring conforms to the inside contour of the insulating shell, which supports the spring as the conductor is driven up into the cone. Requiring no pre-twisting, the wires are automatically twisted together for a secure connection and maximum contact. Fixed spring wire connectors may be used to make branch circuit or fixture wire connections on numerous combinations of solid and/or stranded wire.

A square wire, coiled spring expands freely within the tough plastic shell and can accommodate a wide range of wire combinations. The angled edges of the spring attaches to the conductor as the connector is twisted on for an easily secured joint. The spring applies even pressure over the entire contact area, and provides a low resistance connection and mechanical strength against pull and vibration.