![3.00 mm Magnifying Crystal (27.0 mm to 40.0 mm)](http://perrinwatchparts.com/cdn/shop/products/CR-MAGNIFY30_300x61.jpg?v=1684873516)
Domed top and flat bottom – aka Single Dome - approximate thickness at center is 4.60 mm. This crystal gives a domed look without the need for hand clearance and adds a slight magnification to the dial. This crystal is finished with a polished top edge.