Siglent F503ME - Male 4.5 GHz N-Type VNA Calibration Kit The F503ME and F503FE economy 50Ω N type coaxial mechanical calibration standards include fixed terminations, open circuits, short circuits, and through adaptors, specified from DC to 4.5 GHz. The F503ME and F503FE performance specifications are very similar to the Keysight 85032B/E mechanical calibration kit and it can be used as an approximate replacement of 85032B/E, or use the STD of 85032B/E in network analyzers. Several models available Siglent offers several types of calibration kits in both male and female styles up to 9GHz. The following is a brief overview of items in this series. For more detailed information, please see that product's individual page. Model Frequency Type Connector Impedance Similar F503ME DC - 4.5 GHz OSLT N-Male 50 Ω 85032B/E F503FE DC - 4.5 GHz OSLT N-Female 50 Ω 85032B/E F603ME DC - 4.5 GHz OSLT 3.5mm-Male 50 Ω 85033E F603FE DC - 4.5 GHz OSLT 3.