ID sticker has fallen off some years ago , but It’s a Gitzo.
Flat , plain head with US 1/4x20 threads and reverses to Euro threads. Appears to be aluminum construction. Main section is gray , and the extensions are black. Some use marks can be seen , (see photos) but every shaft works smoothly , and locks.
20 inches when closed , and extends to 61 inches when fully extended.
This was used almost exclusively to hold an additional strobe during wedding photography , so it has little to no weight bearing down on it during its lifetime.