Used in vacuum filtration on a small scale, typically to apply vacuum to a Buchner or other funnel while collecting filtrate. Buchner funnels require either a rubber sleeve, tight-fitting stopper, or similar flexible adapter. Each has a white enamel label spot. These heavy-wall flasks have a short, barbed glass sidearm to attach standard vacuum tubing (inner diameter 10 mm). The contemporary version of these flasks have longer, more cylindrical sidearms and slightly different labeling. This custom bundle comprises two sizes of model number 5360: 5360-25 Fits stopper size #3. Specs (seller measured, not exact): height, 75 mm; maximum width, 56 mm; bottom diameter, 41 mm 5360-50 Fits stopper size #4. Specs (seller measured, not exact): height, 85 mm; maximum width, 59 mm; bottom diameter, 51 mm When it comes to your chemistry, rely on quality name brands. Good glassware is ageless. Ships on the next business day by USPS Ground Advantage (USA only). Item: 2×5360-nn