Feature:1. MULTI FUNCTION: This is a 4GHz transmission reflection vector analyzer that measures the S11 reflection coefficient and S21 transmission coefficient of networks, not only can test the standing wave impedance of the antenna, but also can debug the duplexer, the insertion loss of the filter, isolate and attenuate test cable, shorten the coefficient of antenna amplifier, phase, amplification2. WIDE FREQUENCY RANGE AND HIGH DYNAMIC RANGE: Compared with the previous VNA (10KHz to 1.5/3GHz), VNA V2 vector analyzer provides an ultra wide frequency range of 50KHz‑4GHz, with higher accuracy, in addition, the system dynamic range for this VNA up to 90dB(1GHz) and up to 80dB dynamic range(3GHz); Plus4 VNA features improved shielding for high dynamic range with aluminum housing3. GOOD COMPATIBILITY: The scanning speed of VNA V2 antenna analyzer is 4 times higher than the previous V2 version (400 points per sec); plus support for PC software control, such as for (above 7), for Linux, for OS X, VNA can be better at measuring frequency better compatible with PC and antenna measurements. Flip display for your convenience, you can flip the display by following the steps: menu, display, flip display4. LONG BATTERY LIFE: The upgraded vector analyzer has a built in 3200mAh 3.7V lithium rechargeable battery for longer runtime and longer battery life. There is also a battery level LED indicator on the back of the VNA, that is, the battery fuel gauge, the one closest to the CH1 port connector is the lowest level, indicating less than or equal to 25%5. COMPLETE ACCESSORIES: VNA V2 Plus4 is the original version (software update f