1st Visible sign of puberty in males is

Tanner's staging in Males Stage I : Testicular size < 4ml Stage II :  Sparse hair growth Scrotum and testis (>4ml) enlarge Stage III : Hair growth darkens Penis grows in lenght Stage IV : Hair growth becomes dense and coarse Scrotum and penis continues to grow Growth spurt occurs Stage V : Hair growth extend to inner thigh Genitalia reaches adult size