Atkore Allied Tube & Conduit CKR-250KON 2-1/2" Raintight Compression Coupling

Yes. The CKR-250KON is a raintight compression coupling, rated for use in wet locations, and it is also concrete tight so it can be run in a slab pour or a concrete wall without grout working into the raceway. That combination is why it gets specified for exterior EMT runs and below-grade or embedded work rather than a plain set-screw coupling, which is dry-location only.

It joins 2-1/2 inch EMT, one length to the next. Compression couplings are sized to the trade size of the tubing, so a 2-1/2 inch body only accepts 2-1/2 inch EMT ends. For any other run size you need the matching trade size coupling, not a reducing fitting.

It comes down to where the raceway runs. A set-screw coupling is for dry, indoor locations only. The CKR-250KON is a compression type, raintight in wet locations and concrete tight, so use it anywhere the run is outdoors, exposed to weather, washdown, or embedded in concrete. Indoors and dry, either type will serve; wet or poured, the compression fitting is the one that passes.

The CKR-250KON is built with heavy steel walls, not a light die-cast body. For a 2-1/2 inch run, where the tubing itself carries real weight and the fitting can take a knock during rough-in, that matters on exposed industrial and parking-structure work.

Order manufacturer part number CKR-250KON. That is the Allied Tube & Conduit 2-1/2 inch raintight compression coupling; the CKR prefix is the raintight compression coupling series and 250 is the 2-1/2 inch trade size.

The blue compression nut is an identification feature. On a job where raintight and standard fittings are both in the same gang box, the blue nut lets the installer and the inspector pick the raintight coupling out at a glance instead of reading stamps on every fitting.