The DP798WH is a white PP plastic 20-410 smooth skirt dispensing treatment pump with 4 inch dip tube and clear plastic overcap (0.2 cc output). Treatment pumps are fitted with a clear overcap to prevent accidental dispensing. This closure fits containers with a 20-410 neck finish. The first number is the diameter of the container's opening (in mm). The second number refers to the thread/style/depth of the closure's skirt. Dip tubes can be trimmed to fit smaller shorter containers.