1. Nozzle: bayonet (half bayonet aluminum, full bayonet aluminum), the screw is all plastic, but some have a layer of aluminum cover and a layer of anodized aluminum on it.

2. Pastic lotion pump: the vacuum and the straw are all screw ports. A layer of anodized aluminum cover can also be placed on the screw cap and head cap. Divided into two types: sharp-billed and duck-billed.

3. Hand washing pump: The diameter is too large, and they are all screw ports. A layer of anodized aluminum cover can also be placed on the screw cap and head cap. Generally, there are steps with threads, and those without steps are with left and right knobs.

Length measurement: By length of straw (from gasket to end of hose or FBOG length). Exposed length. And the length measured from under the hood (equal to the length from the shoulder to the bottom of the bottle).

Specification classification: It mainly depends on the inner diameter of the product (the inner diameter is the diameter of the innermost end of the pump) or the height of the large circle.

Nozzle: 15/18/20 MM all plastic is also divided into 18/20/24

Lotion Pump: 18/20/24 MM

Hand Pump: 24/28/32(33) MM

Large circle height: 400/410/415 (just the simple specification code not the actual height)

Note: Specifications and classification expressions such as: Lotion pump: 24/415

Measurement method of measurement: (actually, the dose of liquid that is expended at one time by the nozzle) has two methods: peeling measurement method and absolute value measurement method. The error is within 0.02g. The measurement is also distinguished by the size of the pump body.