Size:MAGNETIC STIR BAR Style:3.3 BOROSILICATE GLASS A convenient classroom set of borosilicate glass Erlenmeyer Flasks with a set of 3 Magnetic Stir Bars. 5 piece Flask Set consists of one each of 50ml, 150ml, 250ml, 500ml, and 1000ml Flasks. 3 piece Magnetic Stir Bar Set, PTEF, Pivot Ring, consists of one each 12x7mm, 25x7mm, and 35x7mm. The 3 stir bars included can accommodate all flasks sizes within this set as well as other larger flask sizes of all brands. If you have any questions or concerns, please contact us. We are happy to make it right!