The previous owners of our home had left a tap dripping in our cloakroom sink, which over time had left a large, stubborn hard water streak / stain where limescale had built up. Various attempts to remove the mark with a range of products, homemade remedies and brute force all failed so thought we would give this a go. What an absolute gem of a product - sprayed generously onto the mark, left for about 15mins & it was gone with a quick wipe of a cloth. A marvel - will 100% be using & buying again as we live in an area with very hard water. Thank you Lakeland.