The 20 mm natural LDPE orifice reducers are available here in a large option of 5,000 per case pack. These orifice reducers limit the amount of product that a bottle will dispense at one time, through its tight fit and 4.9 mm orifice hole. These inserts are perfect for liquids that only need small amounts to be effective such as inks, dyes, food coloring, oils and more.