For engines 1200-1300cc
1st cam diffuser diameter-23mm 
2nd cam diffuser diameter 24mm 
 
Diffuser/auxilary Venturi has been increased, 2nd throttle made mechanically-driven, air and fuel jets replaced, acceleration pump performance increased, cold start adjusted.
Makes the engine breathe easier on medium and high revs. Easy installation.
VAZ 2101 21011 21013 2102 2103 2104 2105 2106 2107 RIVA 1200 1300