How does Fu Guang Shuxiang send books to prison?

Nowadays, due to security problems, many prisons prohibit sending parcels directly. If you want to send them, there are two ways.

First, meet directly through the interview room. Self-study books can be brought in.

Second, if it is inconvenient for you to go in person, you can send the book to his sub-prison (squadron) to discipline the police, and then help him bring it in. This is also allowed.