Single Quadrant Radius Chart This Mylar Overlay displays Radius in only one quadrant on one chart. Increments per magnification are as follows... 10X Mag - .010" increments 20X Mag - .005" increments 50X Mag - .002" increments 100X Mag - .001" increments 13.5" Diameter Mylar Overlay fits both Mitutoyo Optical Comparator models... PH-A14 PH-3515F This item is made to order, so the lead time for shipping is approximately 1 - 2 weeks after receipt of order. Please indicate your Lens Magnification when adding to cart.