HOLEPLUG sodium bentonite is a naturally occurring Wyoming sodium bentonite clay that is sized and graded chip material used to seal and plug earthen boreholes. HOLEPLUG bentonite is available in two particle size grades: • HOLEPLUG 3/4" grade (100% of particles pass through 3/4" screen; all particles retained on 3/8" screen) • HOLEPLUG 3/8" grade (100% of particles pass through 3/8" screen; all particles retained on 1/4" screen)