Smart Handcuffs

Smart Handcuffs (インテリ手錠) are a technology developed in Academy City developed for the purpose of restraining suspects.

Principles
They are sturdy handcuffs but, as their name suggests, they have additional features. When another person tries to forcibly remove the handcuffs, another smaller set of handcuffs can come out to restrain them. There are at least two sets of additional handcuffs. After the activation of the smaller ones, a tiny speaker within the handcuffs informs the following: "The unlawful release prevention program has activated. Any vibration, impact, electrical shock, or heat over a certain level is seen as an unlawful method. Upon detection of such a method, various methods of restraint such as tear gas will be used.", further indicating additional functions.