The DP155 is a white PP plastic 40 mm smooth skirt foamer dispensing pump with 4.5 inch dip tube (1.5 cc output). When depressed, foamer pumps convert the liquid contents of the container into foam. This makes this an ideal closure for liquid soaps and cleansers. This pump can be locked in the up position, preventing accidental discharge. This closure fits containers with a 40 mm 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. This pump is made of polypropylene (PP), which means it has a high heat tolerance level and an excellent resistance to fatigue. Dip tubes can be trimmed to fit smaller shorter containers.