NT-98D

The NT98 was the first Magnetron to go into production.

The E1188 was the first British sealed off tube, only 6 being made.

It was improved to become the E1189, which was accepted for military use as the NT98.

Unstrapped, aprox. 10kW output on the S band and not very efficient and somewhat rare.

Thanks to Bob Comeau for this image and info.