When you demand high performance, look to the 3M Highland Color-Coded Block Fork. This fork terminal is both reliable and safe, and provides an ideal fit every time. It's made with electrolytic copper for good conductivity and a tin-plated finish for corrosion resistance. The butted-seam barrel is insulated with vinyl and withstands temperatures of -40 to 221 degrees F (-40 to 105 degrees C).