INDICE What is Denier (D) What is Thread Count (T) What is GSM What Ripstop means What DWR means What PU (Polyurethane Coating) means What the water column (mm) means What Silnylon or Silpoly means Why these specs matter When you look at the specs for an outdoor product, it’s common to see terms like these: Nylon Ripstop 7D 190T Polyester Polypropylene 150 GSM If you’re not familiar with them, they can be pretty confusing. But these specs tell you a lot about a fabric: its strength, weight, density, or water resistance. If you want to better understand what you’re buying, it’s worth knowing what these abbreviations mean. I’ll explain it simply. What is Denier (D) Denier (D) is a unit that indicates the thickness of the yarn used in a fabric. In technical terms: 1 denier equals the weight in grams of 9,000 meters of yarn. The higher the denier number, the thicker the yarn. That usually means the fabric will be: Stronger More durable But also heavier For example: Nylon 40D → stronger and heavier Nylon 15D → lighter but less durable In ultralight gear, it’s common to find fabrics in the 7D to 30D range, especially in tents and sleeping bags. What is Thread Count (T) Thread Count indicates the number of threads in a square inch of fabric. In other words, it measures the fabric’s density. For example: 190T Polyester means the fabric has a total of 190 threads per inch. The higher the number, the denser the fabric usually is. That typically implies: Higher strength A tighter weave More weight What is GSM GSM stands for Grams per Square Meter (grams per square meter). It’s a direct way to measure the weight of a fabric. For example: 150 GSM → lightweight fabric 300 GSM → thicker, heavier fabric This measurement is widely used for materials that aren’t traditional woven fabrics, like some sleeping pads or synthetic materials. What Ripstop means Ripstop isn’t a material, but a way of building the fabric. It works by integrating thicker threads in a grid pattern within the cloth. This prevents a small cut or tear from spreading through the fabric. That’s why many outdoor materials use constructions like: Nylon Ripstop Polyester Ripstop DCF Ripstop This system increases durability without adding much weight. What DWR means DWR stands for Durable Water Repellent. It’s a treatment applied to fabrics so water beads and sheds off the surface instead of soaking in. This doesn’t mean the material is fully waterproof, but it does help repel light rain. With use and washing, a DWR treatment can lose effectiveness over time. What PU (Polyurethane Coating) means Many tent and backpack fabrics have a PU (polyurethane) coating. This coating is applied to improve the material’s waterproofness. In the specs, it usually appears together with a waterproof rating. What the water column (mm) means A fabric’s waterproofness is usually measured in millimeters of water column. This value indicates the water pressure the fabric can withstand before it starts to leak. For example: 1.000 mm → basic rain resistance 2.000 mm → suitable waterproofness for tents 3.000 mm or more → high waterproofness In modern tents, it’s common to see values between 2.000 and 4.000 mm. What Silnylon or Silpoly means You’ll also often see names like Silnylon or Silpoly. This indicates the type of coating applied to the fabric. Silnylon → nylon coated with silicone Silpoly → polyester coated with silicone These coatings improve waterproofness and the material’s strength. Why these specs matter Understanding these specs will help you read product sheets more accurately and know what you’re actually buying. When you see something like: 20D Silnylon Ripstop 3000 mm you already know it means: 20D → yarn thickness Silnylon → nylon coated with silicone Ripstop → tear-stop reinforcement 3000 mm → waterproof rating In other words, a fairly complete description of what the fabric is like.
How to Understand Fabric Specifications in Outdoor Gear
Learn what fabric specifications mean in outdoor gear: Denier, GSM, Ripstop, DWR, water column, and more.
When you look at the specs for an outdoor product, it’s common to see terms like these:
Nylon Ripstop 7D
190T Polyester
Polypropylene 150 GSM
If you’re not familiar with them, they can be pretty confusing.
But these specs tell you a lot about a fabric: its strength, weight, density, or water resistance.
If you want to better understand what you’re buying, it’s worth knowing what these abbreviations mean.
I’ll explain it simply.
What is Denier (D)
Denier (D) is a unit that indicates the thickness of the yarn used in a fabric.
In technical terms:
1 denier equals the weight in grams of 9,000 meters of yarn.
The higher the denier number, the thicker the yarn.
That usually means the fabric will be:
For example:
In ultralight gear, it’s common to find fabrics in the 7D to 30D range, especially in tents and sleeping bags.
What is Thread Count (T)
Thread Count indicates the number of threads in a square inch of fabric.
In other words, it measures the fabric’s density.
For example:
190T Polyester means the fabric has a total of 190 threads per inch.
The higher the number, the denser the fabric usually is.
That typically implies:
What is GSM
GSM stands for Grams per Square Meter (grams per square meter).
It’s a direct way to measure the weight of a fabric.
For example:
This measurement is widely used for materials that aren’t traditional woven fabrics, like some sleeping pads or synthetic materials.
What Ripstop means
Ripstop isn’t a material, but a way of building the fabric.
It works by integrating thicker threads in a grid pattern within the cloth.
This prevents a small cut or tear from spreading through the fabric.
That’s why many outdoor materials use constructions like:
This system increases durability without adding much weight.
What DWR means
DWR stands for Durable Water Repellent.
It’s a treatment applied to fabrics so water beads and sheds off the surface instead of soaking in.
This doesn’t mean the material is fully waterproof, but it does help repel light rain.
With use and washing, a DWR treatment can lose effectiveness over time.
What PU (Polyurethane Coating) means
Many tent and backpack fabrics have a PU (polyurethane) coating.
This coating is applied to improve the material’s waterproofness.
In the specs, it usually appears together with a waterproof rating.
What the water column (mm) means
A fabric’s waterproofness is usually measured in millimeters of water column.
This value indicates the water pressure the fabric can withstand before it starts to leak.
For example:
In modern tents, it’s common to see values between 2.000 and 4.000 mm.
What Silnylon or Silpoly means
You’ll also often see names like Silnylon or Silpoly.
This indicates the type of coating applied to the fabric.
These coatings improve waterproofness and the material’s strength.
Why these specs matter
Understanding these specs will help you read product sheets more accurately and know what you’re actually buying.
When you see something like:
20D Silnylon Ripstop 3000 mm
you already know it means:
In other words, a fairly complete description of what the fabric is like.
Would you like us to notify you when we publish another article?