A year ago we had most of our 2 inch drain pipe replaced in our 40 year old house and the plumber recommended using a natural drain treatment to keep the pipes clear. This product fits the need being all-natural microbes that simply need to be activated by warm water to digest household fats, oils, grease, etc. The solution is then poured down each house drain (sink, tub, laundry) at bedtime.
This product is safe for all types of drains (metal or plastic). It did not harm any of the drain covers or other hardware, and left a light scent similar to a carpet cleaner or mild laundry soap.
No need to worry about any drips or splashes as this product is not harmful to people, pets, or plants. I plan to continue to use this product periodically (label suggest 30-60 days).
DIYBob via Homedepot.com Boise, Idaho November 28, 2015