Different Brass Instrument Valve Materials

There are 3 main materials used in the production of brass instrument valves and they vary by both manufacturer and model. So what difference to they make?
There are 3 main materials used in the production of brass instrument valves and they vary by both manufacturer and model. So what difference to

Specification:, Item Type: Trumpet Valve , Material: Metal, Color: Silver , Package List:, 3 x Trumpet Valve

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Different Brass Instrument Valve Materials

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