What is the recommended stirring bar for StarFish? A variety of different glassware can be used with StarFish. The stirring bar recommended depends on the glassware you are using. For flasks, we suggest: For 500 ml flasks: RR95920: Oval Stirring Bar 40 mm (Pack of 5) For 250 ml, 150 ml and 100 ml flasks: RR99064: Elliptical Stirring Bar 25 mm RE (Pack of 10) For 50 ml and 25 ml flasks: RR98097: Elliptical Stirring Bar 15 mm RE (Pack of 20) RR98091: Cross Shape Stirring Bar 16.5 mm RE (Pack of 20) For 10 ml and 5 ml flasks: RR98075: Cross Shape Stirring Bar 10 mm (Pack of 40)