From 0waste: "Compatible with any spray bottle, these tablets are biodegradable and come in zero-waste/eco-friendly packaging. Just open the package, drop the tablet in hot water, wait 5 minutes for it to dissolve, shake for 30 seconds and toss the packaging into the recycling bin or your compost, easy peasy! This product can be used to eliminate soap scum and grime from shower doors, toilet bowls, tiles and vinyl curtains. One tablet is equal to 700ml of bathroom cleaner liquid. Ingredients: All the ingredients are plant based and biodegradable. Ingredients list: Citric acid anhydrous, Sodium bicarbonate, Sodium percarbonate, Sodium citrate, Sodium metasilicate, Sodium laurel sulfate, Sodium polycrylate, EDTA acid, Fatty alcohol polyxythylene ether." *This product is proudly Zero Waste From Montreal, QC, Canada.