**Check out our grommet/eyelet sizing chart.
Mesh grommets are often used for air ventilation of hats, shoes, tents, crafts and more. Ours are heavy duty brass quality, which will not rust and work great for products exposed to moisture.
Size: 12mm (1/2") diameter, 6mm (1/4") inside hole diameter, Height: 5mm (3/8").
For smaller projects, our hammer and anvil setter; may work fine. For larger volume applications, you may want to consider our heavy duty press machine + appropriate die. We also offer hole cutting tools for pre-punching holes before you set your grommet. While not required -- especially for smaller sizes -- it can be helpful to cut perfect holes beforehand.