Features:Multi-functional digital-display meter can measure the AC voltage and current, active power, apparent power and power factor at the same time. Adopting high strength fire retardant material, safe and reliable. High measurement accuracy, stable performance. Compact size and sturdy structure, easy installation. No external AC transformer is required for measuring current within 99.9A. Simply pass the wire of the measuring loop through the small round hole on the right side of the meter to complete the measurement. Specification:Measurement voltage: AC80-300V, AC200-450V (Optional)Measuring current: AC100A (additional transformer is required if it is greater than 100A)Power supply: no power supply is requiredMeasurement accuracy: 0.5%Overall dimensions: 54 * 80 * 64mm / 2.1 * 3.1 * 2.5in Installation: 35mm din rail installationPackage List: 1* Multi-Functional MeterNote:New-style and old-style are shipped randomly1Multi-functional digital-display meter can measure the AC voltage and current, active power, apparent power and power factor at the same time. 2Adopting high strength fire retardant material, safe and reliable. 3High measurement accuracy, stable performance. 4Compact size and sturdy structure, easy installation. 5No external AC transformer is required for measuring current within 99.9A.