https://www.smithscientific.com/category/products-3250/flasks-3254/flat-bottom-flasks-with-jointed-neck-4546/
Flat Bottom Flasks With Jointed Neck - Smith Scientific
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https://www.calpaclab.com/500ml-polycarbonate-conical-erlenmeyer-flasks-flat-bottom-vent-filter-caps-sterile-1-per-pack-case-12/nst-783111
500mL Polycarbonate Conical Erlenmeyer Flasks, Flat Bottom, Vent Filter Caps, Sterile, case/12
500mL Polycarbonate Conical Erlenmeyer Flasks, Flat Bottom, Vent Filter Caps, Sterile,1 per pack, case/12
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