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Pimples Height: 3.3mm
Pimples diameter: 2.5mm
Aspect Ratio = 1.32

For every ball size (& material) , there probably is an optimal pip length for maximal effectiveness
3.3 mm may be suitable for 44 mm ball (use \d in Japan) but not for the 40 mm ball
2.5 mm to 2.8 mm ay be optimal for 40 mm ball

The aspect ratio of 1.32 may be too low . A value of 1.5 is ideal for 40 mm ball