Bourns’ BVRA1210 and BVRA1812 multilayer varistors with advanced transient energy absorption deliver high surge protection.

[Afroman’s] latest video shows you how to add reverse voltage ... in a diode for protection, but as [Afroman] points out, that wastes power in the form of heat when the circuit is working ...

Fortunately, [Peter] wrote in to give us the details of this low-voltage sub-build ... a connection between the paper clips and closes the circuit on whatever is wired into it.