This powerful yet safe formula will not harm toilets, internal toilet components, plumbing, or septic systems. Use Iron OUT powder or liquid spray first to clean the toilet bowl before inserting a tablet. Simply drop a tablet in the tank and let Iron OUT ATBC do the work for you. A family-owned business that started in 1958, Summit Brands offers highly effective, sustainable, and innovative household cleaning products. Summit Brands began with the distribution of multi-purpose rust stain remover, Iron OUT, and has since branched out to include a broader line of specialty cleaning products under the OUT, Glisten and Plink brands. As category leaders in many consumer segments, Super Iron OUT Automatic Toilet Bowl Cleaner is designed and tested to repel rust and hard water stains with every flush of your toilet bowl. The concentrated formula cleans rust away and repels new stains from forming for at least 45 days per tablet. Simply drop in a tablet and let Super Iron OUT ATBC do the work for you.