Chauvin Arnoux D37N [P01120056A] 30A/300A/3000A AC Current Probe Adapter. The Chauvin Arnoux D37N AC 30A/300A/3000A RMS (3V AC)[F] Current Probe is a non-contact clamp that works with oscilloscopes and other devices that use the BNC interface. This D Series current clamp provides a wide 90mm jaw opening, allowing you to test thick cables and large conductor rails. Furthermore, it provides highly accurate measurements for current and power, alongside exact change, high bandwidth and low-phase displacement measurements. The Chauvin Arnoux device has a rectangular-formed clamp that aids the 90mm jaw size, giving you the chance to measure more equipment. Its True RMS compatibility also allows for exact signal reproduction.