The Keysight 11921E is a high-precision coaxial adapter that provides a connection between a 1.0 mm male and a 1.85 mm male connector and is designed for frequency ranges from DC to 67 GHz. With an insertion loss of 0.5 dB, a return loss of 20 dB and a repeatability of -35 dB (1.0 mm) or -40 dB (1.85 mm), it offers excellent RF performance. The adapter is designed for a maximum continuous power of 10 W and is ideal for high-frequency measurement applications, including on-wafer and coaxial measurements, where the highest precision and reliability are required.