COD VIALS MERC FREE 98VIALS UN 1830. Kit comes in a cardboard box and contains everything needed to perform up to 97 tests (except distilled water): 98 vials and instruction book. Range: 0-15,000 ppm (HR+) Mercury Free Method: APHA Standard Methods, 23rd ed., Method 3500-Cu C-1999. All COD Kits require the use.