Transistor NPN Silicon 75V IC-0.8A TO-18 Audio AMP/switch
The NTE123A (NPN) and NTE159M (PNP) are widely used “Industry Standard” complementary transistors in a TO18 type case designed for applications such as medium–speed switching and amplifiers from audio to VHF frequencies.
 
Full spec sheet: 
https://www.nteinc.com/specs/100to199/pdf/nte123a.pdf