The CRM-100 detects alpha, beta, gamma, and x-radiation. It is designed for general purpose radiation detection including home safety, hobby, and educational purposes. A highly accurate digital display shows readings in your choice of mR/hr, CPM, µS/hr, or CPS. Each pulse also registers visually (by LED) and audibly (which can be muted). A Total/Timer feature allows timed readings from one minute to 40 hours for precise measurement of low level contamination. Note: The CRM does not have an alert feature. If your intended application requires a user-adjustable alert feature, we recommend the Radalert 100 or Inspector Alert.