Surface Mount Termination 10 Watts, 50?. The C20A50Z4 is high performance Alumina (Al2O3) surface mount termination intended as a cost competitive alternative to Aluminum Nitride (AlN). The termination is well suited to all cellular frequency bands such as; AMPS, GSM, DCS, PCS, PHS and UMTS. The high power handling makes the part ideal for terminating high power 90 degree couplers and for use in microstrip circuits. The termination is also RoHS compliant!