Sta-Kon RBB21 INSUL NYLON BUTT SPLICE 16-14 AWG

The RBB21 is sized for 16-14 AWG stranded copper wire on both ends. The blue insulation is the standard color code for that range, so on a job you can spot the right splice in a tray without reading the barrel. Run 12 AWG or 18 AWG and the crimp will not hold properly, you need the splice sized for that gauge.

Yes. It carries UL file E9809. For an inspector that means the splice itself is a listed component, though the installation still has to be made with the crimp tool specified for insulated terminals, as an under-crimped barrel is the usual failure point rather than the splice.

The RBB21 is rated to 105 degrees C, so it handles the elevated ambient inside fixture canopies, motor terminal boxes and attic runs where PVC-insulated terminals start to soften. Nylon insulation is tougher than vinyl against abrasion and cut-through when wires are pushed back into a crowded box.

A butt splice like the RBB21 makes an inline, low-profile connection, which is what you want inside conduit bodies, fixture stems, control panels and anywhere a twist-on connector will not fit or could be shaken loose by vibration. Wire nuts are faster in an open box with three or more conductors. The tradeoff is tooling: the RBB21 needs a crimper, and once crimped the joint is permanent.

The barrel is copper and crimped, which is the connection method used for stranded conductors in control and fixture wiring. Solid 14 AWG building wire is generally joined with twist-on or push-in connectors instead, since a crimp barrel does not deform solid wire reliably.

Country of origin on the RBB21 is the United States, which is what public-agency and federal MRO buyers need documented on domestic-sourcing lines. Order it by the manufacturer part number RBB21.