The HEM581L from Sainty-Tech Communications Limited is a RF Amplifier with Frequency 800 to 2500 MHz, Gain 19 to 22 dB, Gain Flatness ±0.75 dB, Noise Figure 3 dB, Output Power 11 to 13 dBm. Tags: Power Amplifier. More details for HEM581L can be seen below.