The most common are HDPE (high density polyethylene) and PP(polypropylene)
HDPE mesh bags: soft hand feel, good toughness, strong tensile strength, high transparency, more often used in fruit, vegetables and other agricultural products packaging
PP Mesh bag: relatively harder and more durable, but prone to brittleness at low temperatures. Commonly used for seafood, toys, industrial products, etc
When selecting, you can choose based on the characteristics of the packaging (whether it needs to be soft, whether it is in a low temperature environment).