Feature:1. For LoRa antenna that can be used indoor and outdoor, industrial design, durable Radome fiberglass, excellent waterproof and high temperature resistance.2. Compatible with HNT RAK Helium Hotspot Miner V2 V1 Bobcat Miner 300 syncrob is Dragino LPS8 MatchX M2 Pro Longfi LoRaWAN3. At the same time, we use a coaxial extension cable, it is a high value cable with very low performance loss. Note:If it is used outdoors, we recommend that you install it in an open place,If it is used indoors, we recommend that you place it near a window. If there is no signal change when using this antenna for the first time, please turn off the power of the device, then plug in the antenna, and then turn on the power again. Low VSWR:The VSWR of this antenna is 1.1, which is lower than other similar antennas (the closer the VWSR is to 1, the lower the reflection and the better the antenna match)How to choose dBi? Lower dBI: Excellent performance on uneven terrains or hotspot high density areas. Higher dBI: excellent performance on flat terrain and low hotspot density. Middle dBI: ideal for those enorments that enter among others the enviorments described above. What is the rated profit and maximum profit? Rated gain refers to the stable value that the antenna can achieve under normal conditions, and maximum gain refers to the maximum value that can be achieved with the lowest loss and the best environment, but this value is not a fixed value, and the gain often fluctuates. Specifications:Brand: STARFFuction: fixed wall bracketFrequency: 868-930MhzRated gain: 3dbiMaximum gain: 4.5dbiAntenna height: 25cmAntenna connector: NImpedance female connector: 50 Ohm Extension cable: 1m low cable lossAdapter: as the picture shownOperating temperature: -20°С-+80°СStorage temperature: -30°С-+85°СPacking:1 x Antenna1 X Cable1 X Adapter(as the picture)Note:Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!Manual measurement, please allow 1-10mm error. Thank you for your understanding.