how to disassemble the swivel on leash?

i'm a newbie to the hardware part and had already searched the FAQs but no help...
anyway, i would like to disconnect the wire from the surfing leash's swivel to make a custom leash for myself(and also to research)
but i'm not certain about the structure of the swivel, can anyone provide some ideas?
(the connection part in the red circle as shown in figure below)

anyway, i would like to disconnect the wire from the surfing leash's swivel to make a custom leash for myself(and also to research)
but i'm not certain about the structure of the swivel, can anyone provide some ideas?



(the connection part in the red circle as shown in figure below)