Specially formulated to be continuously present in your water lines and to keep lines clean. An effervescing tablet is added to a self contained water bottle each time it is refilled. Weekly shock treatment are not necessary. Purging water lines at the end of the work day is not necessary. Achieving clean water can really be that easy. Available in 2 sizes. A standard tablet treats 700-750 mls and a 2 liter tablet treats 2 liters. Premixing a gallon with two of the 2 liter tablets allows busy offices to "top off" their water bottles to avoid mid-procedure interruptions, saving time and money.