Kavlico has an enviable pedigree of many years supplying position feedback for steam turbine applications at nuclear power stations worldwide.  These are units that perform day in and day out in harsh environments for many years.  The key advantages of Kavlico products are a non-contacting design and rugged construction. Typical applications include stop valve position feedback.  Please see our list for cross reference part numbers to find the part you need.  Kavlico also repairs existing hardware here
LVDT