Mesh, Nitex Nylon 630um 45" Roll 1 Foot/Unit Ideal for catching adults when collecting embryos, this Nitex nylon mesh has a 630�m pore size and 53% open area. Sold by the contiguous lineal foot from a 45" roll. From Genesee Scientific's extensive line of Drosophila products, this mesh is sold by the lineal foot, so you can order just as much as you need.