Magic Inhibitor is a device used to temporarily block a magic-user's ability to cast spells. It works similarly to the Silencer potion and traps the magical energy inside the spellcaster's body.
Magic Inhibitor was invented at the turn of the 20th century in the United Kingdom by Matthew Kelly, a professor of magical technology at Oxford University. He was researching new ways of proecting soldiers from magical attacks and accidentally found a way to block person's magic. The first person on which the device was used was Kelly's lab assistant, Paul Bell.
The inhibitor is used mostly by law enforcement as a tool used when arresting magic-users. Most often it is used by the BMID to apprehend blood mages. Another group which uses this technology is the military. They are using it to keep the prisoners-of-war in check and during interegations.
In most countries inhibitors are produced in state-owned factories or by companies with which governments have signed contracts. Currently, the devices are mass-produced but every single inhibitor must be tested. These tests are always run by government official accompanied by representatives of law enforcement and military.