Bolex "Surefire" handgrip

[David T. Nethery]

I recently picked up one of these Paillard-Bolex "Surefire" handgrips . It works well. I like the handle with the built-in cable release. It balances better with my older and lighter non-reflex H8 than with the heavier H16 REX4 .

 

But I'm wondering if anyone knows about the supposedly "reversible" screw mount ? The description in Andrew Alden's 'Bolex Bible' says that it has a "reversible mounting screw which has both Congress [3/8"] and Kodak [1/4"] threads" , but I can't find any way to release the mounting screw from the handle to reverse it. Mine has a 1/4" screw , which works fine for me , but I'm just trying to figure out if Alden's description has it wrong or if I am not understanding how to release it so that the screw can be reversed .

 

Another description of it here: http://bolexh16user.net/SurefireHandgrip.htm also says "The screw that tightens the grip to the camera is one of the reversible mounting types and has both 3/8" European thread and 1/4" Kodak thread." (although that web page may just be repeating information from the 'Bolex Bible' ? )