THE QLTY LAB Lime Scale + Rust Remover is an extremely effective industrial grade formulated for home use. It is aqueous-based rust scale and lime remover that is used to remove lime deposits on shower doors tubs tiles and fixtures such as faucets and towel hangers. It is composed of non-flammable materials and does not contain mineral acids that cause problems with building corrosion. It also safely removes rust scale and corrosion from both ferrous and non-ferrous metals such as iron steel copper bronze brass aluminum cast iron and stainless steel. TQL 664 is safe to use everyday and it will not affect aluminum stainless steel rubber or plastic parts. It comes in an easy to use trigger spray bottle. Simply point dab with sponge wait for few minutes and wipe clean.