A mechanical pencil for using a lead effectively includes a tip pipe for protecting a lead. The device includes a shell and a heat-generating component. Ion milling is conducted at a grazing angle to the surface of the layer upon which the pinned magnetic layer is fabricated, where the ion beam is oriented in the direction of the desired magnetization of the pinned magnetic layer. The power transmission mechanism further includes a transmission shaft extending between the engine and the rear wheel mechanism. The amount of tear fluid can be quantitatively measured by measuring the interval D. The electrical contacts are spaced so that an electrical connector of a medical lead being inserted will span the distance between the electrical contacts and thereby maintain a physical connection with both electrical contacts at one time.