The CD4013B device consists of two identical, independent data-type flip-flops. Each flip-flop has independent data, set, reset, and clock inputs and Q and Q outputs. These devices can be used for shift register applications, and, by connecting Q output to the data input, for counter and toggle applications. The logic level present at the D input is transferred to the Q output during the positive-going transition of the clock pulse. Setting or resetting is independent of the clock and is accomplished by a high level on the set or reset line, respectively.

Logic Type: D-Type Flip-Flop (2 independent circuits per chip)
Supply Voltage Range: 3V to 18V DC
Package Type: 14-pin SOIC (Small Outline Integrated Circuit), surface mount
Operating Temperature: -55°C to 125°C
Clock Trigger: Positive-edge triggered
Maximum Clock Frequency: Up to 24 MHz (typically 16 MHz at 10V supply) 

Independent Controls: Each flip-flop features independent data (D), set, reset, and clock inputs, alongside complementary Q and Q̄ outputs.
Asynchronous Operation: Set and reset functions override the clock and occur when their respective input lines go high.
Toggle and Counter Modes: Connecting the inverted output (Q̄) back to the data input (D) allows the device to act as a toggle or binary counter. 
Static Operation: Retains state indefinitely when the clock level stays in a fixed high or low state.