IDEAL Industries 30-3629 High-Temp Wire-Nut® Wire Connector, Model 73B® Black, Box of 100

Yes. IDEAL lists Models 71B, 72B and 73B as rated for use in air handling spaces, so the 73B black high-temp Wire-Nut is the one to reach for above a drop ceiling or in a return air plenum where standard connectors are not acceptable.

That is what it is built for. The 73B is a high-temp connector made to withstand the heat build-up found in high-wattage lighting fixtures and signs, which is where ordinary connectors soften or discolor. Fixture whips, ballast compartments and sign cabinets are its normal home.

No - they do different jobs despite both being called connectors. The IDEAL 30-3629 is a Model 73B High-Temp Wire-Nut twist-on wire connector, a splice cap that joins conductors inside a box or fixture and is approved for bonding and grounding applications. The Leviton 8319-C is a hospital grade NEMA 5-20R connector and the Bryant 8269T is a hospital grade NEMA 5-15R connector; both are cord-end receptacle bodies that terminate a flexible cord so a plug can be inserted. If you are splicing fixture leads, the twist-on is the part you want.

A twist-on connector such as the IDEAL 30-3629 Model 73B is intended for splices inside enclosures, including air handling spaces and high-wattage fixtures where heat builds up. For a wet or washdown termination you want a sealed device: the Pass & Seymour Turnlok 27W Series is a 20A watertight connector rated NEMA 4X/6P, and the Bryant WPC Series is a weatherproof wiring connector fitting. Those seal the connection against water ingress, which a twist-on cap does not do on its own.

Yes. IDEAL calls out fine stranded wire as a strong application for this connector. The spring is a fixed, square-wire design, which bites and holds stranded conductors rather than letting them back out of the shell.

It is. IDEAL states the connector is approved for bonding and grounding applications, so you can use it on equipment grounding conductor splices as well as line and neutral work.

Two different jobs. The 73B is a twist-on splice cap for joining conductors inside a box, fixture or sign, including bonding and grounding splices, and it is rated for air handling spaces. The Leviton ML2-C is a midget connector, a cord-end device body rather than a splice cap, as are the Leviton 8319-C hospital grade NEMA 5-20R connector and the Pass & Seymour Turnlok 27W watertight connector. If you are making up a cord or a portable drop you want one of those; if you are splicing conductors you want the wire nut.

Not interchangeable. The black 73B is IDEAL's high-temp line, sized and sprung for heat-exposed splices and air handling spaces; the everyday colored Wire-Nut caps are general purpose and are not the ones IDEAL calls out for those conditions. If a fixture or sign is cooking your connectors, the 73B is the swap.

The IDEAL 30-3629 is supplied as a box of 100 Model 73B black High-Temp Wire-Nut connectors. Two peers are also packaged in hundreds: the Leviton ML2-C midget connector for electrical wiring comes in a pack of 100, and the Leviton 8319-C hospital grade NEMA 5-20R connector comes in a pack of 100 in black. The IDEAL item is a twist-on splice cap for in-box wiring; the two Leviton items are cord-mounted connector bodies, so stock them for different tasks rather than as alternates.

The ML2-C is a Leviton midget connector for electrical wiring sold in packs of 100 - the name refers to a compact connector body, not to a twist-on splice cap. The IDEAL 30-3629 is the Model 73B High-Temp Wire-Nut with a positive grip shell meant to be twisted on with the fingers and a fixed square-wire spring, and it handles fine stranded wire. If your need is a small-gauge splice inside a luminaire, the 73B is the matching part.

Those cover separate stages of the circuit. The Leviton 15W33 is an industrial grade straight blade connector, 3-wire 2-pole, rated 125V 20A, used at the end of a cord to accept a plug. The IDEAL 30-3629 Model 73B is a twist-on wire connector for joining conductors, rated for use in air handling spaces and built for the heat found in high-wattage fixtures and signs. A plant doing both cord assemblies and fixture splices typically stocks both.

The 30-3629 part number is a box of 100 Model 73B black high-temp Wire-Nut connectors. It is the quantity most contractors buy for a fixture retrofit or a sign job rather than a counter card of a dozen.

No tool needed. The 73B has a positive grip shell meant to be twisted on with your fingers, which matters when you are working one-handed inside a fixture canopy or a sign raceway.