Printed in brown ink on top of the glass envelope.
Printed vertically in green ink on glass envelope.
overall: 1 1/8 in x 1 1/8 in x 3 in
This is a pentode vacuum tube with a loctal base. Pin 5 is missing by design. The object was accompanied by an index card that had "NR3127 - Box 1 - #15; SYLVANIA; 5-7AK7" in letters printed with a red felt tip pen and "Small pentode used in Whirlwind and SAGE computers,"