Whats inside speaker cable boxes?

[NJPOLKER]

I am wondering what is inside those boxes on high end speaker cables. At the cost I assume its gold but not sure. Can you guys/gals shed some light on what they incorporate?

example
http://www.audiogon.com/cgi-bin/cls.pl?cablspkr&1228539477&/MIT-Shotgun-S2-BiWire-10'-Pair
Thanks Drew

[Polkitup2]

I recall someone cutting open an expensive Transparent "network box" and it was filled a 10 cent resistor and rubbery goop.