Borosil Amber Volumetric Flask with I/C Solid Glass Stopper Class A (5648)Borosil Amber Volumetric Flask with I C Solid Glass Stopper Class A (5648) Each flask engraved with individual serial number and supplied with certificate of calibration traceable to National standards Manufactured from 3. 3 borosilicate USP Type I glass with an amber coating on exterior surfaces to facilitate use with light sensitive solutions White enamel inscriptions Product Code Capacity ml Tolerance ml Stopper Size Quantity Per Case 5648005 5 0.