Relax Oxy Shock. Spa water 1000 litre - 20g. Spa water 1500 litres - 30g. Spa water 20000 litres - 40g. Full instructions for use are on the bottle. Zone D - HS, IV41-49, IV50, IV55&56, KA27-28, KW15-17, PA20, PA41-49, PA60-78, PH42-44, ZE, Isle of Man & Channel Islands.
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