This is an entry-level portable active small loop antenna. It adopts the mainstream ne592 chip scheme in the industry. It has small volume and strong performance. It is suitable for all kinds of radios and SDR receivers. It is convenient to set up indoors and outdoors. It is a welfare product for enthusiasts who can't set up large outdoor antennas. Amplifier chip: NE592 Battery model: 6f22 (9V) Working voltage: 6 - 10V Working current: 14 - 16mA Ring diameter: 30 - 40cm Battery life: 20-50 hours (depending on battery capacity) Recommended receiving band: Medium wave: 526.5khz - 1606.5khz Short wave: 3 - 30MHz FM: 87 - 108MHz Aviation: 116-136mhz Note: 1.only for RX. can't TX 2.Without 1x 9V battery Color: Black Material: ABS Package Contents: 1 set x Active Small Loop Antenna Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.