This lens is perfect for cutting thicker materials, with a larger field of view this beam carries its power further and straighter than its smaller focal counterparts. The flexibility of this lens extends to engraving objects that are not completely flat. This is also a great lens for full wrap engraving on tumblers.
As a rule of thumb, the following applies to the focus lenses: the more detailed the graphics, the shorter the focal length in laser engraving. The thicker the material to be laser-cut, the greater the focal length should be.