This chastity device is much more advanced version of the classic KTB chastity device, which effectively prevents erection. It is comfortable while the penis is flaccid, but it "bites" when getting aroused for whatever reason, preventing any forbidden activity. Spikes of the cage are blunt, they do not cause any injury. Some marks might remain for a few days after longterm use, but it is absolutely safe to wear. It also has a removable 7mm penis plug with pee hole. / Lockable penis plug - it cannot be removed without the key.