Are Etherwave's pitch and volume antennas empty inside (pipes) or solid?

Hello every one!

Is there anyone can help me figure it out?

Are Etherwave's pitch and volume antennas empty inside (pipes) or solid?

Thank you!

Also I would like to ask you about assembling it: on the pics that I saw on internet, disassembled antenna looks like just pipe, but also there are pics of antenna with some ring on the ends and nut. How those ring are mounted to antenna?

Thank you very much!

"Are Etherwave's pitch and volume antennas empty inside (pipes) or solid?"

"Also I would like to ask you about assembling it: on the pics that I saw on internet, disassembled antenna looks like just pipe, but also there are pics of antenna with some ring on the ends and nut. How those ring are mounted to antenna?"  - Heorhii

The antennas are 3/8" plumbing piping.  The nut and "ring" are plumbing compression fittings, the "ring" is a ferrule.

I think now all right...