Hot Tub Descaler, Spa Scale Inhibitor Remover, Prevention, Universal - 1L. Chlorine Mini Tablets for Hot Tub/Spa, Pool Floater, Chemical Dispenser, 1kg. Easy Colour Match System - Dip the water quality testing strip fully into the water, remove and hold horizontally then read against the coloured chart on the side of the bottle in 30 seconds.
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