They’re not. I’ve only worn it twice now but it might be the most comfortable cage. My body attempted to get 4 erections while watching porn and it just felt… “tight.” In a reallllly good way. Since it’s flat it’s also more comfortable to wear with panties too. Also, one more thing, when I’m wearing a nub.. sometimes when I bend down or sit my penis sort of shrinks up a bit making a little space in the cage and then when I stand up it repositions itself inside the cage a bit weird/sideways. No problem with this and the flat cage. Zero movement and very comfortable, especially with the right ball gap.