12 sets of 4 oz White HDPE Plastic Boston Round Bottles and Pumps. 24-410 neck finish. The boston round bottle is distinctive in its classic shape. Characteristic of the boston round are its rounded shoulders and rounded base. HDPE is marked with the resin identification code of 27. HDPE is slightly more resistant to impact than PET bottles and provides greater temperature resistance and a very good water vapor barrier. Light-weight bottle used for lotions of all type.and is used for products containing essential oils. This item comes with a 24-410 neck finish pump and cap.