Nylon Insulated Snap Plugs and Receptacles Bullets for wire sizes 22 - 14 AWG with bullet sizes of 0.156 inch and 0.180 inch. Deformation-resistant nylon insulation material is molded onto barrel and is translucent to allow easy inspection of wire connection. Brazed barrel seam will not separate under pressure or operating stress. Funnel entry. Industry standard color-coding. Rated to 600 volts.