Sapphire Instruments is a privately owned Taiwanese corporation. It was founded in 1988 with the vision to provide testing instruments of high quality and high performance. Our sole shareholder and general manager, Mr. Jeff Hsu, who was a former assistant professor in a university, developed the first handheld active differential probe in the world. Our company has developed a series of active differential probes and established our status as a professional producer in this field. Recently, we are a worldwide supplier of active differential probes.   Due to increasing business development, Sapphire Instruments established a subsidiary company Sapphire Instrument Subic Bay, Inc. on 2006 and transferred the production line to Subic Bay, Philippine. The department of Research & Development still stays in Taipei. The Sapphire Instruments Subic Bay, Inc. insists headquarters¡¦ quality policy in order to achieve the first and foremost objective, the costumer¡¦s satisfaction. In Sapphire Instruments Subic Bay, Inc. we produce a series of high voltage and high frequency differential probes.   As a professional manufacturer of active differential probes, Sapphire Instruments provides a complete set of products. All of our products can directly draw power from oscilloscopes or use batteries and mains adaptor. They are divided into two categories: first, the differential probes for high voltage power measurement. Among this category, we provide models of input voltage of up to 7000Volts and of bandwidth up to 100MHz. And the second, the differential probes for high speed signal measurement, among this category, we provide models of input voltage of up to (+/-) 15Volts and of bandwidth up to 800MHz.   In the future, we plan to develop a new high voltage active differential probe of input voltage up to 40,000Volts and of bandwidth up to 50MHz. We are also going to develop a new high speed active differential probe of input voltage up to (+/-) 150Volts and of bandwidth up to 1GHz.