The CV1100 is an M-OV Type KTW62 supplied during WWII for RAF use. It is a variable-mu IF kinkless tetrode of the 6K7 class but with slightly more gain. Thousands were supplied during the WWII. This tubular glass version was probably a later product made for replacement purposes.
Not relating to this exact valve but this box shows how service users were notified about the CV numbers for existing types. The sticker dates from 1943 and the CV number is CV1100.
The box has been annotated with the old service code.
The wide glass tube envelope is 28 mm in diameter and, excluding the IO base pins, is 99 mm tall.