26 September 2025

Wire Nuts are Absolete

Before the twist on wire Nut, electricians had to solder wires together, then tape them. Ceramic twist on wire connectors were introduced in the 1920s, by the 1950s they were plastic and the current color codes for the different sizes were established.

Pros and Cons of Wire Nuts.

• Pro: Can be removed to allow reconfigurations.

• Pro: Color coding makes it easy to select the right size nut from a mixed container.

• Con: Some colors are similar, often Orange and Red connectors appear the same, I refer to them as Small Red And Large Red.

• Con: Sometimes a wire will work lose, especially when pushing wires into a box after working on them, but they can work loose over time (typically if they were partially loosened while being pushed in).

• Con: Twisting wires tightly requires effort.

• Con: Take up space in a cramped box.

• Con: When reconfiguring pigtails old twists often need to be straightened out or the wire trimmed.

• Con: The most wires a nut can handle is 6, the more connections in a nut the more likely a loose wire.

• Pro: For household wiring they are much easier to work with than the older alternatives: Screw Terminal Blocks, Push In, and Soldered.

While searching for more compact wire nuts I happened on Wago lever wire connectors. Initially I was skeptical, having previously experienced crimp on connectors (common in automotive wiring) and push in wire connectors.

Advantages of Wago 221 Connectors over Wire Nuts

• See through. Connectors can be visually checked to confirm all wires are properly seated.

• Lever Lock. Holds the wire tight. Can be released if changes need to be made, wires aren’t twisted so don’t need to be untwisted or trimmed to reseat.

• Compact. Takes up less space than twist on connectors.

• Splice Connectors (included in most starter assortments). Don’t require a pigtail to extend a wire that is too short.

• Color Coding is for the wire size. You can see by looking at the connector how many wires it holds.

• Come in sizes for up to 10 wires!

The orange connectors can handle 12-24 AWG in each socket, if you’re working with heavy wire the green connectors are 12 AWG specific and the grey ones are meant for 10 AWG. Most household wiring is 12 and 14 AWG, contractors often only run the heavier 12 AWG which can be used in both 15 and 20 Amp circuits; they do this so they are handling only 1 wire type and don’t have to keep track of which circuit is going to be which amperage, for them the that outweighs the higher cost for 12 AWG and that 12 AWG is harder to bend. 12 AWG and 14 AWG are the only two wires that are commonly mixed so it is important that connectors support this.

Older Push Ins

Working with the type of Push In connector used in auto wiring required tight crimping to make a solid connection, and changes require trimming the wires. If one side failed to crimp, the other side still needed to be cut to retry the connection. The push in connectors for outlets and switches were particularly bad, known for working lose, and once pushed in you had to cut the wire to replace the outlet.

The new lever connections are much better than the old push in connections: they’re see through so you can see that all of your wires are in place, if something does work lose, you can see it without having to take everything apart (as with wire nuts). If you need to rearrange your wires, the ends in the connectors are straight and not twisted, and they lever right out. The old push in outlets used a spring to grab the wire, the lever requires force to lock, making it likely to be more reliable in the long term.

Other Lever Options

There was an earlier Wago Lever Nut which isn’t considered as good as the 221 Series, so make sure you’re getting 221. Other manufacturers are making similar products, but be wary of Push In connectors that might look similar to the lever connectors. Leviton is using a lever on their GFCI outlets, and maybe we’ll see it on regular outlets.