【40W Module with Air Assist 】The 40W module uses compressed spot technology to reduce the focus to 0.08mm * 0.08mm, helping engraver to cut faster and deeper.Easily cut 10mm wood and 8mm acrylic.(Engraving speed: 500-3000, cutting speed: 0-250) 【Rapid Cutting and Engraving】Air assist can speed up cutting and engraving once the proper amount of airflow for a particular material is determined. This is achieved by the means of removing smoke, excess soot and carbonized residue particles. 【Clean Surface】The Air Assist Set uses air to quickly reduce the temperature of the cut material surface, preventing distortion and discoloration to get a clear work. 【Protectation】The air assist set has a stable air output system that blows away the acceptable debris and smoke generated during it work, protecting the head's lens from contamination. 【wide Application】Great tool for engraving wood,paper,leather, glass,acrylic, stainless steel etc. Remember to check your spam folder. Craigslist e-mails often end up there.