Watts WPC Series 10" x 2.5" Pleated Sediment Filter Range up to 10000 ppm Meter ✓ NSF Listed ✓ ISO ✓ NSF Listed ✓ ISO Certified Manufacturing ✓ 5 Year Warranty ✓ Made in USA } The Oakton WD 35624 28 is a precision double junction pH electrode engineered as a direct replacement sensor for the Oakton pH Testr 2 waterproof meter flex wrap:wrap border bottom:1px solid var( slate)