Date of birth
Millwall signed striker Harry from Folkestone Invicta for an undisclosed fee in August 2016.
The striker had been on trial with The Lions since the middle of July and impressed in pre-season friendly appearances against Dulwich Hamlet, Dover Athletic and Greenwich Borough.
Smith, 21, found the net 13 times during Folkestone's 2015/16 title-winning campaign and was also prolific in front of goal when with Sittingbourne in the first-half of the same season.
He was named on the subs' bench for the first time at Port Vale in August and made a dream senior debut on 8th November, scoring two late goals to secure a 3-1 win at Luton Town in the Checkatrade Trophy.
The youngster also netted a hat-trick in the club's 5-2 Emirates FA Cup victory over Braintree Town at The Den in December.