A commonly used basic chemical material. It is used for instance for bleaching and colouring in the textile industry, in degreasing bath, for boilers, piping and drains cleaning and unblocking. We use 0,5 l of hot water for 100 g sodium hydroxide. We will let it works for 30 min and after that we will rinse down it. For better effect we can repeat it. Protect your face and hands! Don’t use for aluminium pipes!