Drainex Instant Cleaner is designed for regular use in drains, grease traps, gullies & pipework to remove excess water. Drainex Instant Cleaner is safe to use the product and will not damage porcelain, plastics, stainless steel, chrome, or ceramics. Easy to use in Bathroom sinks, bathtubs, showers, toilets, kitchen sinks, floor drains, slop sinks, urinals, RV drains. Drainex Instant Cleaner is safe to use the product and will not damage porcelain, plastics, stainless steel, chrome, or ceramics. Add a cup of water and leave for approximately 30 minutes. Flush well with water. Repeat application for stubborn blocks.