Having added an extra cold water pipe run in our utility room, there is a tendency for water hammer elsewhere in the system if taps are turned off with enthusiasm (about the only enthusiasm my son shows about anything!)
I have seen this product
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in the toolstation catalogue and wonder if it is critical whereabouts in the system it is installed. I can see an argument for it to be on the rising main after the meter before any branches off to taps etc but on the other hand could it be almost anywhere as all the pipes are hydraulically linked?
Presumably there is a diaphragm and damped spring arrangement inside?
TIA
Bob