What’s “D” in the Backpack?

Do you often see “300D nylon”, “600D Codura”, “1680D oxford”…on the description card when you choose a backpack? What’s the meaning of the “D”? Most people may regard “D” as “density” or its weight, is that true?

If you are those people who know customized backpacks, you must know “D” is the unit of measurement for fiber. Searching “D” in Encyclopedia, “D” is the abbreviation of “denier”, a unit of fineness, also known as “denier number”, which is the weight in grams of 9000 meters of filament. For example, 600D means that the weight of 9000 meters of filament is 600 grams. While 9000 is a standard, but if the length is not 9000 meters? How to calculate? The formula is as below picture:

Is it clear?

Let’s connect with our life and image what’s the fiber of the fabric looks like? The same designed T-shirt, which has a different thickness. Generally speaking, D is a reference to the thickness of backpacks. From the appearance, the bigger D, the thicker silk, the thicker backpack; While the smaller D, the lighter silk, so the backpack is lighter, thinner. For example, a 210D fabric, which has a very fine organization, and generally used as the lining or layer of the backpacks. And fabrics with 900D or 1000D are thicker, abrasion-resistant, more suitable for the bottom of the backpacks.

——Army Backpack 900D Polyester Large Tactical Molle Outdoor Rucksack

• 900D Oxford fabric
• Molle system
• Multiple pockets
• Large capacity
• Adjustable buckles

In backpack customization, 300D and 600D are widely used, while some bags need thicker fabric, such as tool bags, which should use those that have higher D, such as 1000D or 1680D.

——Waterproof Backpack TPU Rolltop Outdoor Sports

• 900D Oxford fabric
• Molle system
• Multiple pockets
• Large capacity
• Adjustable buckles

Now, you must have a clear mind about the D in the material description, you can roughly know the thickness and durability of the backpack even if you can’t touch the backpack.