Atkore Allied Tube & Conduit SC125-ICRKON 1-1/4" EMT Set Screw Connector With Insulated Throat

It does. The SC125-ICRKON carries an insulated throat, so conductors bear on a plastic insert rather than a cut steel edge as they enter the box. That is what many jurisdictions and specs call for when pulling insulated conductors, and it saves adding a separate bushing on the box side.

Only if the joint is taped. The connector is rated concrete tight when taped, so wrap the connector-to-tubing and connector-to-box joints before the pour. Set screw fittings are not raintight, so for wet or outdoor locations use a compression (raintight) EMT connector instead.

For dry interior runs, exposed or in walls, the set screw type like the SC125-ICRKON is the normal choice: faster to land, fewer parts, and it grips with staked screws. Go to compression instead when the raceway is outdoors, in a damp or wet location, or anywhere a raintight fitting is specified. For concrete, the set screw version is acceptable if you tape the joints.

Heavy steel walls, not zinc die cast. That matters on commercial jobs where fittings get stepped on and where a spec calls out steel set screw fittings rather than pot metal. The body resists crushing when the tubing is pulled into position.

The SC125-ICRKON is a box connector, so it lands through the knockout and is secured on the inside with a locknut. Plan on a 1-1/4 inch steel locknut for each fitting and a 1-1/4 inch knockout in the enclosure. No bushing is needed on the conductor side, since the throat is already insulated.