This 500ml bottle contains hydrochloric acid at just below the 10% maximum limit that is allowed for retail sale.  The original 30% version is now a REGULATED product and cannot be sold online without a person obtaining an EPP licence from the Home Office.  Business purchases would require ID and other checks before the sale.  This version has no restrictions and is still effective, but requires more time or several applications to be as effective as the old version.
 
Age Verification Required: This product is not for sale to people under the age of 18