I believe this is an accomplishment reward for completing a training regime on GE reactors.
This is a taller mug with a muted personality, with its light maroon (dusty rose?) exterior and unassuming light ivory interior. Even the printing is muted, as the white lettering and logos are more eggshell than snow white. The cup is practically flawless, with no abrasions, cracks, or chips anywhere on the mug. The interior side has a slight horizontal 'defect,' but it is total glazed over, so it was part of the ceramic prior to firing, and not user damage. The underside is embossed with "ENGLAND FPC."