1、Great workmanship and high practicality, good accessories for laser engraving machine 2、Made of excellent aluminum material with red oxide film, which will not easily oxidize 3、Available in two laser head focusing lengths for your choice, meeting your different using needs 4、Come with complete accessories, easy to install and remove, very convenient to operate 5、This lens frame head installation set is suitable for laser engraving machine，very practical Item Type: Laser Engraving Machine Lens Frame DIY CO2 laser head integrated installation kit 20mm mirror focus lens 1060 1040 6040 3050 100W 80W 60W 50W laser engraving cutting engraving machine for Cutte Optical path frame of CO2 laser engraving machine Optical path frame set (all frames do not include lenses) Laser Head Focal Length: Approx. 50.8mm / 2in, 63.5mm / 2.5in The Difference Between 50.8 and 63.5 Focusing Lens Barrel: The female thread of the lower end of the 50.8 focusing lens barrel is shallow, and the female thread of the lower end of the 63.5 focusing lens barrel is deep Lens Diameter: Approx. 20mm / 0.8in The reflector frame can be equipped with dia20mm reflecting lens, and the focusing lens barrel can be equipped with dia20mm focusing lensSize: Approx. 31mm / 1.2in 39mm / 1.5in80 ~ 85mm / 3.1 ~ 3.3in 28mm / 1.1in 26mm / 1in 35mm / 1.4in 21mm / 0.8in 18mm / 0.7in30mm / 1.2in 10mm / 0.4in 58mm / 2.3in 17mm / 0.7in 60mm / 2.4in 1 x 1st Lens Frame 1 x 2nd Lens Frame 1 x Laser Head