Reticle 21mm Whipple Grid 10 x 10 Array .7mm Sq. Overall This Metric Grid has a 10 X 10 Matrix of .7mm X .7mm Squares. One square is further divided into a 10 X 10 Matrix of .07mm Squares. The Grid Line Widths are .001”± .0001” (.025mm±.0025mm).The Pattern is right reading looking through the glass so that the pattern can be in direct contact with the object to be measured.The Reticle Pattern is very durable, double layer, deposited evaporative Chrome/Chrome Oxide, for a reflectivity of less than 5% looking at the pattern. The Patterns on all Reticles manufactured by Max Levy are replicated from Precision Chrome on Glass Tooling under clean room conditions. Click here to download drawing 21mm Compatibility Chart Full Compatibility Chart