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What is 1st Visible sign of puberty in males is and explain in detail?
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