These Corning magnetic stir bars are Teflon®-coated for increased chemical-resistance. Bars are available in 2” x 3/8” in. (5.08 x 0.95 cm) or 1” x 3/8” in. (2.54 x 0.95 cm). 1233W94 stir bars are suitable for use with PC610/620 stirrers while 1233W95 stir bars are for use with PC210/220 and PC-410/420 stirrers.