The SGN21C105MK from Sumitomo Electric Device Innovations is a RF Transistor with Frequency 2.1 GHz, Power 47.5 dBm, Power(W) 56.23 W, Saturated Power 49.5 to 50.3 dBm, Power Gain (Gp) 16 to 17 dB. Tags: Flanged. More details for SGN21C105MK can be seen below.