Prinztronic SR99P

3 v (2x AA batteries).

Display is 8 digits, green fluorescent in single tube.

4 functions, %, square root.

Main Integrated Circuit - NEC uPD940C (here date coded weeks 15-16 1975).

78 mm x 123 mm x 24 mm.

Made in Japan.
The distinctive style casing with the rounded corners on the right side is a feature of some models from the TEAL (Tokyo Electronic Applications Laboratory Ltd.) company, so this model may have been manufactured by TEAL.

About 1975.

Inside showing the VFD (Vacuum Fluorescent Display) tube and the NEC μPD940C calculator IC.