Designed and manufactured by Nooelec in North America. Impeccable quality and full 2-year warranty!. Always-on, 4.5V bias-tee with independent ultra-low-noise power supply and 250mA power capability allows you to power nearly any active antenna circuitry without messing around with drivers or software. Same form factor as the other devices in our NESDR SMArt series, which means no USB occlusion issues--run devices side-by-side without messy extension cables or adapters, even on embedded devices like the Raspberry Pi!. Unmatched price & performance--redesigned PCB reduces noise by an average of a full 3dB! Includes all the same fantastic features as the rest of the NESDR SMArt series, including an ultra-low phase noise TCXO, with a guaranteed <0.5PPM tolerance out-of-the-box. This is at least 4x more accurate than units advertised as containing 1PPM TCXOs, which have up to a +/- 2PPM initial offset.