I purchased a CB600s before Christmas, and at £30 I should of known it couldn't be the real thing? However I was wondering if the original CBs comes with hollow rings as pictured bellow? I've had nothing but trouble with the grove leaving an imprint on my scrotum that hurts like hell after a while. I've already filled in one grove with silicone sealant and having to fill in the other today. I know what they say, "buy cheap buy twice" but I purchased the cheapest device I could to see if I could handle being locked in a CB again, it turns out I can so am now modifying the device so I can stay in it for longer periods.
No the real deal is not hollow.... Or well mine wich is brand new is not. Another thing to mention is that the material might not be good for your body. The company who have sold you this item have måde a decission to cheat the inventors of cb, steal their name and products and with that moral why should they care about their consumers well being. With that in mind I would like everyone to think about what kind of business you are supporting.
Rings are $20US from the manufacturer. Use the Chinese knock-offs to find what size fits best, then order an authentic ring. I started off in the same boat as you, falling for a discount priced imitation. After using it for about a year, pieces started to break, so I started ordering replacements from AL Enterprises as needed. They actually break quicker than the Chinese parts did, and come with no warranty. http://cb-x.com/cb6k3.html
Your not the only one, seems some retailers are selling them marked as CB6000, but when they arrive they're not what they seem. A few people commented on Fetlife saying the exact same thing.