The RF4-10 is a large ring terminal insulated with high dielectric-strength nylon for wire size #4 AWG. These ring terminals have funneled barrel entry, deep internal serrations, and overlapping seams. Length 1.76 inches, .56 inches width, maximum insulation .510 inches, bolt hole #10. The terminal is high-conductivity electrolytic copper, electro-tin plated, with color-coded insulation, rated for 105°C max temperature. Installing tool TBM6S.