The main difference is of layers in these masks. The N95 mask has 5 layers; on the other hand 3 ply mask has only 3 layers.Thus N95 mask filters more efficiently than 3 Ply mask.
That is the reason why doctors recommend N95 mask for persons with lower immunity.The quality of mask also depends on the raw material.
We, at Favourite Fab, are determined to provide best quality raw material at reasonable price.We are ISO 9001:2015 certified company with thousands of happy & satisfied customers.