What are dash size and body size?

We can see the Size parameter in the international standard document of the quick connector. The annotation shows that “the size designation corresponds to the nominal size of the hose recommended for use with the coupling, sea ISO 4397”. We can easily understand that the size of the quick connector is consistent with the corresponding hose size.

The hose size refers to the inner diameter of the hose. Therefore, we can easily understand that the body size of the quick connector refers to the inner diameter of the corresponding hose size.

Now we know that a quick coupling with a 1/2″ body size corresponds to the nominal zie of the hose recommended for use with this coupling and the hose’s inner diameter is 1/2 inch (12.5mm).

What is the Dash size?

“Dash size” in the context of quick couplings refers to the inner diameter (ID) of the hose or tube the coupling is designed for, measured in sixteenths of an inch. It’s essentially a standardized way to indicate the size of the quick coupling’s opening.

Here’s a breakdown of how dash sizes work:

  • -1: 1/16″ inner diameter
  • -2: 2/16″ inner diameter
  • -3: 3/16″ inner diameter
  • -4: 4/16″ inner diameter (and so on)

For example, a quick coupling marked “-4″ would fit a hose with an ID of 4/16″, which is equivalent to 1/4”.

 

The size would sometimes be too complex to mark on the products, so people simply put a dash no. refers to the diameter of a hose, tube, or fitting in 1/16″ increments.

Each dash size corresponds to a progressively larger diameter, measured in sixteenths of an inch. “-1″ is 1/16”, “-2″ is 2/16″ = 1/8”.

Because too many customers confuse body size and dash size, and most ISO standards for quick connectors use body size to express it, we accepted the suggestions of many customers and started to use mm in the new website and catelogues. The mm size is used to describe the product number, and inches are used to describe it on the website to facilitate customer search.

It’s important to note that the dash size only refers to the hose or tube diameter, not the overall size of the quick coupling itself. Different quick coupling types and brands may have varying outer dimensions even for the same dash size.

HOSE I.D. (Inches)
All EXCEPT Transportation & Refrigerant Hoses Transportation & Refrigerant Hoses
DN Dash No. Inches Millimeters Inches Millimeters
5 -3 3/16 5
6 -4 1/4 6,3 3/16 5
8 -5 5/16 8 1/4 6,3
10 -6 3/8 10 5/16 8
13 -8 1/2 12,5 13/32 10
16 -10 5/8 16 1/2 12,5
19 -12 3/4 19 5/8 16
25 -16 1 25 7/8 22
32 -20 1-1/4 31,5 1-1/8 29
38 -24 1-1/2 38 1-3/8 35
51 -32 2 51 1-13/16 46
-40 2-1/2 63 2-3/8 60
-48 3 76

DN = Nominal DIN Size