This showerhead model Z 10 (HM) by Cotto is using between 5 and 6 litres per minute, depending on the pressure.
Tap Aerators - Unfortunately, it is often not possible to obtain spare aerators for those broken or blocked from salt deposits. Therefore, in many hotels with low flow taps, once the aerators become unusable it is necessary to replace the whole tap. This may not be done due the cost implication (when the tap itself is still in good condition), which can result in “water saving” taps displaying excessive flows (as a result of the missing aerator). It is essential to make sure that spares are available for any fixtures you purchase, or if not, that the supplier offers a warranty.
The pictures below indicate the difference in flow with and without an aerator (note the amount of air bubbles in the first picture). The measured flows were 5.8l/min and 11.2l/min respectively.