🔎 UNIDENTIFIED Need help with the ID and age it

[savinghistoryalway.s]

 

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[Mud Hut]

I believe that is an old-style bleeder valve.

 

[Mackaydon]

Reminds me of a vintage pressure cooker release valve.
Don in SoCal

 

[gldnbrew]

Reminds me of a vintage pressure cooker release valve.
Don in SoCal

I will second that

 

[Sandinmypants]

It does look like a pressure cooker lid; I just recall them having the open arrow on top