It's good to say how much space there is, but there is no place to mark it. Generally, you can just look at what d is. Is it three-dimensional cotton? It is heavier and more durable.

Generally, it is 12~ 15D, and the whiteness of three-dimensional hollow fiber is better. Filled cotton of 48*74 specifications, above 1.8 kg, can be safely used. Remember that it is clean cotton 1.8 kg.