Pack of 6 tablets for Raritan's Purasan EX waste treatment systems & older Purasan systems which have been retrofitted with the new style tablet basket. Raritan Purasan EX dispenser tablets Tablets are for all Raritan PST12EX and PST24EX waste treatment systems For use with 41-135RFK retrofitted older Purasan units Each tablet life is approximately 75 treatment cycles New style tablets no longer require haz-mat shipping Cannot ship via air freight - must ship ground only Contains 6 refill Purasan tablets