Welch Allyn diagnostic equipment is used for a variety of medical purposes, including assessing and monitoring a patient's vital signs, conducting basic physical examinations, and diagnosing various medical conditions. This equipment includes devices such as blood pressure monitors, stethoscopes, otoscopes, ophthalmoscopes, and other tools for examining the heart, lungs, ears, eyes, and other body systems. It is commonly used in hospitals, clinics, and healthcare practices to aid in the diagnosis and treatment of patients.