There are basically three ways to convey the spacing of industrial wire cloth; mesh count, opening or center to center distance.
Mesh count
The number of openings in a lineal inch measured from the center of one wire to a point one inch distant. Figure A depicts a 4 x 4 mesh count. Mesh Cloth Specification Tables.
Opening
The space between adjacent parallel wires usually measured in inches. When designating the specification by opening it is often referred to as space cloth. Figure B depicts a ¼” opening space cloth. Square Opening Space Cloth Specification Tables.
Centers
The center to center distance is measured from the center of one wire to the center of the next adjacent parallel wire. Figure C shows an example of 1” x 1” c-c or center to center mesh. Center to Center Specification Tables.