The size refers to the height of the main piece.
The dimensions of the main piece:
Size 1 - H: 25 mm / 1 inch x W: 16 mm / 0.6 inch
Size 2 - H: 32 mm / 1.25 inch x W: 20 mm/ 0.8 inch
Size 3 - H: 38 mm / 1.5 inch x W: 24 mm / 0.9 inch
We used these stamps to create texture.