Sta-Kon RC2577F INS NYL FEM-250 DISC 12-10 LEN 0.8

The RC2577F takes 12-10 AWG stranded wire, which is what the yellow nylon insulation tells you at a glance on a Sta-Kon terminal. If you're terminating 16-14 or 22-18 gauge, this barrel is too large to get a reliable crimp, so step down to the blue or red equivalent instead.

The flag body turns the wire 90 degrees to the mating tab instead of running straight off it, so the conductor lays flat alongside the terminal block or switch rather than needing clearance straight out in front. That's the reason to pick a flag over a straight female disconnect when you're working behind a motor cover, inside a shallow junction box, or stacking terminals close together.

The conductive body is brass, and the sleeve is nylon/polyamide rather than vinyl. Nylon is the tougher of the two insulated terminal materials, better at resisting abrasion, crush during crimping and higher operating temperatures, which is why it's the usual choice for motor leads and appliance wiring over PVC-insulated terminals.

The RC2577F is the female half only. It slips onto an existing 1/4 inch male tab on a device, or onto a separate male disconnect if you're splicing two wires. For a wire-to-wire connection you'll need to order the matching 250 series male disconnect for 12-10 AWG separately.

Open top means the insulation sleeve is slotted over the crimp barrel so the die contacts the metal directly through the opening. You crimp it with the barrel visible, which lets you confirm the conductor is fully inserted before and after crimping. Use a die sized for 12-10 AWG insulated terminals, not an uninsulated or open-barrel die.

Country of origin is the United States, which matters if you're buying against a Buy American or domestic-preference requirement on a government, school or healthcare project. The part number to cite on the submittal is RC2577F.