Typical Age Range

This stage begins when growth in height ceases and lasts for the remainder of an adult’s life. On average, it typically begins around age 17, but can start as early as 15 or as late as 20.
Characteristics and Changes During Stage 5:
Even after stage five is reached, changes continue to occur for several more years.
Growth
Growth in height stops. This is the primary marker for the start of stage 5.
Genitals

The scrotum is at its adult size. The testes are longer than 1 3/4 inches (4.5 cm) long, measured along the long axis, or over 20 ml in volume.
Penis has full adult characteristics.
Hair
Pubic hair covers the groin and the inner thighs.
Chest hair develops.
Full facial hair develops.
Body
Muscles are easily developed.
Shoulders widen to give a typical male physique.
Chin widens, giving a squared-off look.
Attitude
The brain continues to develop, reaching typical adult thought patterns by about age 24. During the early part of stage 5, males tend to be rash in their behavior, acting without fully considering the consequences of their actions.