[Hallicrafters] Hallicrafters R-42 Reproducer

[DW Holtman]

Hello,

I recently aquired an R-42 reproducer. It works great and looks so-so. My question to the group is, on the back on either side of the speaker terminals are two jacks that look like speaker jacks. They look like original equipment. However, I have never seen a speaker with headphone jacks on the back. Any information would be great. 

Thank you in advance.

73's
DW Holtman
WB7SSN