I am assuming you are talking about a fabric made from either 1200 or 600 denier yarn.
The thickness of the yarn in 1200 denier is twice that of 600 denier, which also implies the fabric will be rougher and ofcourse stronger.
If you are looking for strength, 1200 is better. If you want a smoother finish fabric, choose the 600 denier.
Hope this helps.
Deviprasad
Nylon is more durable than polyester. Also, when comparing 840 denier to 600 denier of the same fabric, the 840 denier is thicker, rougher, more coarse and stronger than the 600 denier. So, on both counts, the 840 denier nylon is more durable. If you look at the following link, the tan soft dog crate is made of 600 denier polyester and the colorful soft dog crates are made of nylon.
"2400 Denier Polyester and 900 DenierMicro-Polyester fabric"
Though I haven't used either of these myself but EVA- reinforced polyester will be the better option
The ballistic nylon will be a higher denier (thickness of the thread). Also will be shiny/glossy compared to the matte finish of polyester. Ballistic nylon will be much more durable and much less likey to tear or scuff. You can get higher denier polyester (900, 1200, 1800) which will be better for wear and tear. The price will reflect this however as 600d poly is low to mid price point whereas the others are higher.
Denier polyester is fabric and the higher the number, the thicker and stronger it is. 210 would be thin like silk.
nylon
600 x 300 denier is slightly less quality than 600 x 600. The weave is also different
1500 denier, the threads are more dense and closer together thus they are more durable.
In both cases, the "D" stands for the word "denier", which is a measure of the fineness of the material. Specifically, the word refers to the weight (in grams) of 9,000 meters of the fiber from which the material is made. In simpler terms, it means that a higher denier fabric is stronger and more durable than the same type of fabric with a lower denier rating. However, when comparing two different types of fabrics, such as polyester and nylon, it is important to note that because each fabric has different weights, 600D polyester fabric is not equal to 600D nylon fabric in terms of strength. In general, nylon is a stronger fabric type than polyester, and 420D nylon fabric, for example, is actually stronger than 600D polyester
200
smell a poo
no denier mean the density and fibre of the fabric