Delta Epsilon portable borehole loggers draw on a legacy of building logging systems in use around the world for more than four decades. Our borehole logging systems enjoy a hard-earned reputation for outstanding quality and performance. As the founders and former owners of Mount Sopris Instruments and operating for more than a dozen years as Delta Epsilon Instruments, Inc., we bring unmatched experience and dedication to the process of making portable borehole logging systems. Without compromise or frills, Delta Epsilon borehole loggers are designed to work reliably anywhere, anytime, even under the most demanding circumstances. Delta Epsilon has an equally long history designing and producing radiation detection instruments which are in use in many countries around the world.