CASIO Pocket-8s

Japan- 1975

Four functions,
"Its release was accompanied by a machine that looked a little like a hip flask. This machine was a Pocket 8S ( which may explain the Flask look) it had no memories or square root key but it did percentages. The CPU was a MicroPD974C and it had an 8 digit flouro display."
Ray Mackay, Old Casio Calculators

Source: Ray Mackay

X-Number World of Calculators