The HEM388D-4 from Sainty-Tech Communications Limited is a RF Amplifier with Frequency 20 to 600 MHz, Gain 21 to 23 dB, Noise Figure 0.6 dB, Output Power 19 to 20.5 dBm, Output Power 0.08 to 0.11 W. Tags: Power Amplifier. More details for HEM388D-4 can be seen below.