This part is a kind of semiconductor called 74LS161.

Function of this product has BCD DECADE COUNTERS/ 4-BIT BINARY COUNTERS.

Manufacturers : Motorola

Image and pinout :

Some of the text within the PDF file :

BCD DECADE COUNTERS/ 4-BIT BINARY COUNTERS The LS160A / 161A / 162A / 163A are high-speed 4-bit synchronous counters. They are edge-triggered, synchronously presettable, and cascadable MSI building blocks for counting, memory addressing, frequency division and other applications. The LS160A and LS162A count modulo 10 (BCD). The LS161A and LS163A count modulo 16 (binary.) The LS160A and LS161A have an asynchronous Master Reset (Clear) input that overrides, and is independent of, the clock and all other control inputs. The LS162A and LS163A have a Synchronous Reset (Clear) input that overrides all other control inputs, but is active only during the rising clock edge. BCD (Modulo 10) Asynchronous Reset Synchronous Reset LS160A LS162A Binary (Modulo 16) LS161A LS163A SN54/74LS160A SN54/74LS16 [ ... ]

74LS161 PDF Datasheet Download