My Cavity Filter for the APT Weather Satellites on 137 MHz band.   

This filter was  obtained from a fellow GEO member, it is made by AFL and the quality is excellent. It weighs quite heavy! It is designed using aluminum as the base metal. As most raw metals are inherently lossy, filter housings are silver plated for improved electrical characteristics and current flow. Aluminum  resonators are used to minimize frequency drift over temperature.