Cover slips are manufactured from the highest quality borosilicate hydrolytic class 1 German glass. They have excellent resistance to chemicals and are ideal for neural tissue culture and hard-to-attach cells. These cover slips are exceptional for florescence and confocal microscopy. Sold in packages of 1oz.Please Note:12mm Diameter will fit in a 24 well plate; CLS-3500-02415mm Diameter will fit in a 12 well plate; CLS-3500-01225mm Diameter will fit in a 6 well plate; CLS-3500-00.