Weekly Extreme Sudoku Competition for Dec 13 to Dec 19

Number 743, Extreme
by Crosswords Ltd. December puzzle packs Now Out!. Thanks for supporting our site.
Future Puzzle - will be submitted on the relevant day
1 2 3 4 5 6 7 8 9
A
B
C
D
E
F
G
H
J
3       7       4
              7  
      3 9 2 6    
    4 5     2   7
  3           6  
6   1       9    
    8 9 3        
  4     1        
1       5       8