Are Sub (all gold model) 16618k center links solid or hollow (like on 16613)?

[sevykor]

For the past several years, I have been asking a specific question on various boards, experts, etc. The answer has always been 50/50 in respect to a yes and no answer. This tells me that about 50% of the people get the answer wrong. SO, I would like to ask the question here at Rolex Forum.
Question: Are the center 18k gold links on the Submariner Model 16618 (that's the all gold model) Solid or Hollow? Here's the trick however. The Sub 2-tone 16613 is obviously hollow because it's apparent from looking at the side of the center links. The design of the all-gold 16618 has a gold side wall on the center links, but does that mean it's solid or can it still be hollow? Please give me your best guess (unless of course you are 100% certain of the answer). I tried to find a good photo if the 16618 side, but still looking. Thanks ALL!