One piece split-core current transformer clamp with selectable primary ratings of 300 A, 400 A, 500 A, or 600 A (600 A max). This item is a single unit. Split-core design for easy installation around live conductors without disconnecting power. Key benefits - Accurate current measurement for energy monitoring, load analysis, and system monitoring - Flexible ratings: choose 300 A, 400 A, 500 A, or 600 A to match your measurement needs - Single-unit, compact clamp suitable for tight electrical enclosures - Compatible with standard meters and data loggers that accept CT input Use scenarios - Add metering to an existing installation without rewiring or power disruption - Monitor total or feeder currents in commercial or industrial panels for energy management - Retrofit panels to upgrade monitoring and protection schemes with a split-core CT clamp