Feature: 1. 0.96IN DISPLAY SCREEN: Mini automatic antenna tuner, with 0.96in organic light emitting diode display, support USB charging. 2. EASY OPERATION: This automatic antenna tuner case requires no assembly and is developed by N7DDC for automatic tuning. 3. EXCELLENT COMPONENTS: Using excellent 1000V high voltage SMD capacitor, C channel capacitor, and advanced PIC chips. 4. VOLTAGE AND FREQUENCY: The working voltage is 10‑15VDC, the working frequency range is 1.8‑55 MHz, and the application range is wide. 5. ALUMINUM ALLOY: Made of aluminum alloy material, light weight and corrosion resistance, has good heat dissipation effect. Specification: Item Type: Mini Antenna Tuner Material: Aluminum Alloy Model: ATU-100 Working Voltage: 10-15VDC Display: 0.96in Organic Light Emitting Diode Operating Frequency: 1.8-55 MHz Battery Model: 1350mAh 3.6V lithium battery (built in battery) USB Charging Current: 1A Maximum Working Power: 100W Maximum Measurement Power: 150W Tuning Start Minimum Power: 1W Minimum Measurement Power: 0.1W Step for Measuring Power Below 10W: 0.1W Step for Measuring Power Above 10W: 1W Power Measurement Accuracy: 10% Maximum Setting Inductance: 8.4uH Inductance Minimum Setting Step: 0.05μH Maximum Setting Capacity: 1870pF capacitor Minimum Setting Step: 10pF. Package List: 1 x Antenna Tuner1 x USB Cable Note: 1. Insufficient adjustment may occur within 5W, so do not lower than 5W.2. It is recommended that the maximum power should not exceed 30W during tuning. (It can be set to 100W after tuning, and work at this power, otherwise it is easy to burn)3. You need to use 9‑12V to start the ATU‑100. If you use a power bank or computer USB port to output power, you cannot start the ATU‑100 because their voltage is too low.