Features: Effectively blocks 87.5 108MHz broadcast with high inductors, ensuring clear reception for sensitive devices like aviation radios and without external power. tuned circuitry and construction deliver 40dB attenuation on frequencies while maintaining <1dB insertion loss across 25 1300MHz operating . Essential for radio engineers and hobbyists using scanner receivers, Deploys instantly between antenna and receiver in electromagnetic challenged environments like areas or near transmitter . Compact passive band stop filter features optimized impedance matching and grade PCB for stable across 40°C to +85°C conditions. Specifications: 1. this notch in series between your receiving device and the antenna. 2. the device's antenna to the xxOUTPUT end of the notch. 3. the antenna to the xxINPUT end of the notch. 4. that the is firm, it can effectively filter out in the frequency band. Package Includes: Notch x 1pcs note: 1.Please allow 0-1cm error due to manual measurement. Be sure you donot mind before bid. 2.Due to difference between different monitors, the picture may not reflect the actual color