Stable trajectory
We know that a stable trajectory is important, especially for long strikes or when sending the ball down the field as the goalkeeper. To ensure very good stability, we have changed the construction of the outer cover. Traditionally designed with 32 panels, we created the F550 with 24 identical panels. This improves the ball's stability in the air and makes it nicer to kick.
Weight
Between 350 and 390 g (Size 4)
Circumference
Between 63.5 and 66 g (Size 4)
Sphericity
Average measured variation: maximum 1.5%
We measure the ball's sphericity at 16 different points and assess the recorded discrepancies.
If the discrepancy is greater than 1.5% (FIFA PRO Standard), our engineers are tasked with improving the sphericity to ensure a consistent bounce.
Minimal pressure loss
We inflate the ball to the recommended pressure (meaning 0.8 bar).
72 hours later, the ball must not lose more than 15% of its pressure, meaning approx. 0.1 bar. The pressure after 72 hours must, therefore, be at approx. 0.7 bar.
This also means that it is quite normal for a ball to lose pressure after a few days.
Water absorption
We simulate rainy playing conditions in a lab, leaving the ball to sit in 2 cm of water on a pivoting support whilst subjecting it to 250 compressions.
By the end of the test, the ball must not have absorbed more than 15% of its weight, or approx. 60 g for this F550 in size 4.
Bounce
Between 135 and 155cm with a maximum difference of 10cm between the ball's highest and lowest bounce. Each ball is dropped 10 times on a steel plate from a height of 2 metres.
Shape and pressure retention
The most stringent test we put this ball through is the shooting machine test.
Withstands up to 2500 shots against an inclined concrete surface at 50 km/h at a distance of 2.5 m.
At the end of the test, we check:
- the ball's general state: stitching must withstand this test
- the circumference: it must not have increased by more than 1.5 cm
- the sphericity: it must not have varied by over 1.5%
- the pressure: the ball's loss of pressure must not exceed 0.1 bar
Design
Our design team watched football players in action on the pitch to develop this Hybrid ball.
This ball is a hybrid as it combines the comfort of machine stitching with the durability of hand stitching.
We also used a bladder with thread winding (2 km of thread is wrapped around the bladder) to ensure lasting inflation and better sphericity.