CM4371 AC/DC Current Clamp MeterHioki clamp meters are best in class measuring devices incorporating Hiokis expertise in current sensing technology. Model CM4371 is a 600A True RMS clamp meter that features stronger jaws, a broader 25 to 65C operating temperature range, and an IP54 dustproof and waterproof enclosure to enable professionals to work quickly in tough situations including the development, repair, and maintenance of equipment and devices such as electric vehicles.