The state issued one.

"Now let us see what we are working with here. Vince please remove your shorts." The teacher asked as he flushed. His cheeks beet red as he slowly began to pull down his shorts. He looked like a deer caught in the headlights as he exposed his soft brown cock and his thick delicious thighs. He looked at the teacher and gulped as she nodded and reached behind her.
"Now let us pick which one to use... one, two, three! We will use the state issued one first!" She said as she quickly attached a tight silver ring to the base of his dick. He let out an eep of shock as he felt his balls constrict before she pushed the front end of the cage onto his dick making him groan as it snapped shut! Forcing his already tiny dick into a smaller enclosure forcing him to wince in discomfort as he gulped loudly. He instantly felt the pressure on his dick as his sensitive cock tried and failed to escape the cage that it was **** into!
"It's too tight!"
"That is precisely the point! It is made to be uncomfortable as possible without causing any pain! Now what you may not know about this cage is that you cannot achieve orgasm with it! One of the features of it is that it constricts around the balls to the point that at most you might leak a bit but you will never have a proper orgasm! Now this concludes the lesson on state male chastity! Mister Vince please take a seat."
"B-but the cage... it's still on..."
"Oh that! What about it?"
"It's not supposed to stay on is it?"
"Well yes it is supposed to be, it's meant for extended duration confinements sometimes even permanent! Now please have a seat or you will be disciplined." She said her cock throbbing under her dress as he gulped.
"But how am I supposed to get it off?"
"You just need to go to the nearest state sanctioned male chastity office and inquire about getting it removed. Now as long as you do not have a criminal record you should get it off in two to three weeks. Now sit!" She ordered as Vince pulled up his shorts face beyond flushed as the tiny silver cage ground uncomfortably into his dick as he walked back to his seat flushed as he felt the eyes of every futa on him like he was a piece of meat and they all lions.