From cooking extracts to essential oils, the 4 oz. clear Boston round glass bottle with black cone lined cap can be used for storing virtually anywhere. The traditional design of the Boston round bottle is attractively complemented by the clear glass and black cone lined cap used in this design. To help prevent spills and leaks, the black cone lined cap has a tight fit but is still easy to twist open. This bottle makes a great package for handmade gifts or can be easily labeled for products intended for sale.