This lovely artificial sunflower bush stands 38cm/15" high and has 7 very realistic fake sunflower heads on it. 
4 of the flower heads have an approximate diameter of 12cm/5" and the other 3 have a diameter of 7cm/3"
There are sunflower leaves surrounding the flowers to make a complete and instant display.
The sunflowers and leaves are made of a polyester/silk mix and I would not recommend using this sunflower arrangement outside as it is not UV stable so some colour fading would happen over time.

2 left - the home page explains https://www.plantsenhance.com/