Sta-Kon RC482 INS NYL RECT RNG TERM 12-10 No8 YEL

The RC482 is sized for 12-10 AWG stranded copper wire, which is the yellow color code on nylon insulated terminals. Run it on 14 AWG or smaller and the barrel will not grip reliably; for 16-14 AWG you want the blue-coded size instead.

It carries UL file E9809 and is rated 600 V, which covers normal line voltage control, lighting, and branch circuit terminations in commercial work.

A closed ring like the RC482 has to come off the stud to be removed, so it cannot vibrate loose or slip out from under a backed-off screw. That is what you want on motor leads, grounds, and anything subject to vibration. A fork terminal slides out sideways and is faster for service work where you are pulling the same conductor repeatedly. Both land on a No. 8 screw.

The barrel is copper, so use it on copper conductors only. Copper terminals on aluminum wire create a dissimilar metal connection; aluminum needs an AL9CU rated lug with the appropriate compound.

Use an insulated terminal crimper with the yellow-coded nest for 12-10 AWG. Matching the tool nest to the terminal color is what produces a crimp that meets the UL listing conditions; pliers or a non-insulated die will split the nylon sleeve or under-compress the barrel.

The rectangular ring tongue gives you flat parallel sides, so the terminal sits square in a tight terminal block channel or between barriers and resists twisting when the screw is torqued. Round tongues are fine on open studs but can rotate as you tighten.

Nylon insulation is tougher than vinyl against abrasion and crush when you are pulling a harness through a raceway or stacking terminals in a crowded enclosure, and it resists cracking when the barrel is crimped. The yellow sleeve also tells anyone working the panel later that it is a 12-10 AWG termination.

Country of origin on the RC482 is the United States, which is what government and institutional buyers with domestic preference language typically need documented.