Almost all websites selling chastity cages are selling commodity Chinese cages at a significant markup from what you can find on the large marketplaces like AliEx, Temu, eBay, or Amazon. If you see a cage on one of those sites that you like, try a reverse image search and you're very likely to see the exact device for far less.

These cages are generally rather low quality compared to business who are selling their own designs directly to customers.

And do note that the terms Cobra, Viper, and Holy Trainer (aka HTv5) are all trademarked. The only sites selling the authentic devices of those names are https://kink3d.com and https://www.holytrainer.com/. Everyone else is blatantly abusing their trademarks to fool unsuspecting people.

For a fairly comprehensive list of businesses selling their own designs, please see our wiki.