This probe is precision made of Delrin® and flash chrome plated steel. It differs from the IEC and UL standard probe because the jointed finger is 10mm longer and there is no simulated palm. The rest of the dimensions are in accordance with IEC and UL standards. A special disk for the metal finger is also required by GR-1089 requirements. Both the disk and the finger are certified to meet the GR-1089 requirements. The unit includes a banana jack in the handle to check continuity, as required. This product includes certificate of calibration.