What component is used to secure the lead in a back-wired device?

The clamping plate is the correct component used to secure the lead in a back-wired device. This component functions by providing a firm grip on the wire, ensuring that it is held securely in place, which is essential for maintaining a reliable electrical connection. The clamping plate helps to prevent any movement of the wire that could lead to intermittent connections or electrical failures.

In the context of back-wired devices, the clamping plate ensures that the wire is inserted properly and securely, allowing for safe operation. Its design allows it to adapt to different wire sizes and types, making it versatile for various electrical installations.

The other components mentioned do not serve the specific purpose of securing leads in back-wired devices. While they might have important roles in overall device stability or support, the precise function of lead securing is specific to the clamping plate.