4 In1 Filter Passive Filter 4 Bands LC Filter for RF Signal Radio Antenna SDR GPSDO Signal Source and Other Devices 4 in 1 Filter: All popular receivers, radios, SDRs, and Malachite can be used together. Good products are worth buying._x000D_ This product contains four sets of band-pass filters. The filters are divided into 4 frequency bands. The P1 filter is 0.5-1.5MHz, which is suitable for medium-wave radio listening. The P2 filter is 4.5-12MHz, which is suitable for short-wave and low-frequency bands._x000D_ As well as the use of 40-meter amateur frequency bands, the P3 filter is 12-30MHz, which meets the use of shortwave high-frequency bands, as well as the use of 20-meter, 15-meter, and 10-meter amateur frequency bands. The P4 filter is FM broadcast frequency, 88-108MHz. The four-in-one filter can be used with a one-to-four active splitter to provide pre-filter functions for SDRs, radios, and receivers._x000D_ Malachite, pre-filter, makes up for the design of the all-metal aluminum shell malachite radio without pre-filter, reducing interference in frequency bands such as medium-wave and short-wave FM broadcasts._x000D_ The filters are divided into four groups: 0.5-1.5MHz, 4.5-12MHz, 12- 30MHz, 80-110MHz, can be used with a 1/4 splitter to achieve simultaneous reception of multiple channels and frequency bands. Material: Aluminum alloy_x000D_ colour: black Package Contents:_x000D_ 1 x Passive Filter_x000D_ 1 x Machine foot pad _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_