Training key (which also acts as a sounder, but this was not its intended purpose). The trainee had to follow the movement

of the key with his (her) wrist.

In the picture the cover has been removed to show the two solenoids used to actuate the key arm.

The key arm has engraved a crown, between the letters “A. M.” (Air Ministry )

Understood to be manufactured by Creed and Co. of England.