Poolmaster 22242 2-Way Test Kit with DPD Tablets and Case - Basic Collection For maintaining proper water chemistry Tests for Chlorine and pH Includes round vial test block DPD tablets test for Free Chlorine levels and Phenol Red tests for pH Phenol Red is for use with 2 or 3-Way Test Kits Only - not to be used with 5-Way Test Kits (Note: Phenol Red is not the same as Solution #2 Phenol Red - DO NOT interchange) Comes complete in polyethylene case