Greisinger gak 1400 working calibration set greisinger gak 1400 p the greisinger gak 1400 is a working and calibration set for all ph meters p p what s in the box br buffer capsules gph 4 0 5x gph 7 0 5x and gph 10 0 5x br plastic vials gpf100 3x br refill electrolyte 3mol kcl electrolyte kcl3m 1x br cleansing solution grl100 pepsin 1x p greisinger gak 1400 working calibration set