Ideal for a watercooling radiator (static pressure)

This is my second NF-F12 PWM.
The first was used for a former 120mm radiator toilet, I went to a toilet and homemade erformant and customized with a 240mm radiator, so I needed a second identical Noctua.
Compared to my Noctua NF-S12A PWM silencer case, however, it generates vibrations. I found that NF-F12 all have a turbine that turns "not so round", it thus generates vibrations that travel transversely or parallel to the attachment of the fan (if you understand me ...) . The use of additional sound insulation is advisable for it to be inaudible at low rpm: I cut thin slices of foam placed at the fixation.
From the engine side is perfect, no clicking noise, so a good bearing. It can even start at very low speed (296rpm)
The regulation is precise: no speed change when I fixed him a manual speed test

However, it is unacceptable to have paid postage (2,76euros), it becomes more expensive than other stores. So this is the last time I buy a fan here. Free shipping costs are increased from 15 euros to 25 euros minimum purchase is scandalous for this kind of article.