TTL logic, plastic case and part of the 74 series of devices which were released in 1966 and became the industry de-facto standard.
Look inside any electronic equipment from the 1970's ~ 1980's and it is very likely you will find some 74xx devices.
NATIONAL SEMICONDUCTOR
Type: 74157
Part #: DM74157N
Function: Quad 1-line-to-4-line data selector/multiplexer
16 pin DIL plastic
NEW Old Stock
Always stored and these will be supplied in a suitable ESD tube
NEW Old Stock
