A może aluminiowe

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aluminium-vs-zinc-anodes/
Zalety aluminiowych anod, cytat ze strony powyżej
Weight: Aluminium is significantly lighter than zinc, by a factor of 2.5. Al anodes are lighter to ship and to fit.
Capacity: The electrochemical capacity is more than 3 times higher than of the same mass of zinc (you can protect more with less). See data sheet for aluminium alloyed sacrificial anodes.
Driving voltage: Aluminium anodes has a relatively high driving voltage. This means that it provides better distribution of the current, compared with zinc.
Environment: Aluminium anodes carry a better environmental footprint than zinc anodes. Aluminium anode alloys do not contain cadmium, which is harmful to the marine population.
Cost: Aluminium anodes are less expensive, taking into account the significantly reduced weight requirement compared with zinc.

Tak aluminiowe, ze wzgledu na srodowisko i cenę.
Kupiłam takie, przymierzymy. Jak będzie rokowac, kupię też dużego placka 110.