Use them everywhere!. Removes stains and scuffs on all washable surfaces. Just add water and start erasing!. Each Eraser is re-usable. No need to add other cleaning products. The Flash Magic Eraser Extra Power: your solution for tough, everyday stains. Try it on anything: from grimy baths to greasy microwaves, from crayons on walls to grouting between tiles -even those dirty white trainers! Just add water, squeeze, then watch stains disappear like Magic.