Unusual capacitor symbol

[DMartens]

What kind of capacitors are those highlighted in the attachment? They are 220pF but have different-from-usual symbol? Are they a special kind? How many leads would I expect them to have? BTW ... schematic is from a satellite receiving front-end from the 1980's. 

[selcuk]

Feed through capacitors. A special kind for filtering noise for example.

https://www.digikey.com/en/products/filter/feed-through-capacitors/845

[RoGeorge]

Those are feed-through capacitors, they are used to pass wires through enclosure walls and/or through the metal shielding cans of a circuit.
https://en.wikipedia.org/wiki/Feedthrough
https://www.utmel.com/blog/categories/capacitors/what-is-feedthrough-capacitor