The bottom came off when it arrived. I listed it because I made a mistake with the one-hole and two-hole types. Easily achieve the same cleaning power as a professional bath boiler cleaning company with your own hands. ● Supervised by bath boiler cleaning professionals. Supervised by the General Incorporated Association for Antimicrobial and Mold Cleaning Technology Research Institute. Developed based on the technology of cleaning professionals. ● Maximize cleaning with a dedicated cup. Attach to the re-heating port for powerful cleaning. ● Double the effect with two types of detergents. Removes sebum, soap scum, water stains, and all kinds of dirt, even bacteria inside. Ingredients: Agent A: Sulfamic acid (94%), citric acid Agent B: Sodium percarbonate, sodium carbonate, sodium bicarbonate, antibacterial agent (silver zeolite)