Geevorks 450nm 20W Laser Module with Protective Cover Adjustable Focal Length Laser Engraving Head High Speed Laser Engraver Cutter 3D Printer CNC Router Laser Module for DIY Craft Wood Leather Fabric Paper Cutting Engraving   Professional laser module, easy to install, with lower loss, provides 450nm wavelength, for efficient, precise engraving and cutting of plastic, wood, leather, paper and so on, suitable for a wide range of engraving machines. This is the upgraded version with protective cover, safer e than the old one. Features: Upgraded version: Equipped with adjustable protective cover to protect your eyes, no need to wear extra laser glasses while working, safer e than ordinary laser head. With adjustable focal length (5.5W/ 10W/ 20W, 20-70mm) or fixed focal length (30W, 12.6mm/ 40W, 15mm/ 40W, 40mm/ 80W,40mm). Made of premium quality aluminum alloy casing with great durability. It can engrave paper, wood, fabric, plastic, leather, anodized aluminum, etc. Different laser modules for engraving/ cutting different kinds of material and different thicknesses. Features high engraving speed, low power loss, good stability and superior performance, with fine heat dissipation to extend its service life. Compact and lightweight, easy to assemble, has over 30cm long line. Comes with screws, convenient and simple to be installed on the machine. Wide application, it's designed for laser engraver, laser cutting machine, 3D printer, CNC mill and so on, suitable for DIY lover, CNC engineer, artist and more Note: 1. Avoid eye or skin exposure to direct or scattered laser light. 2. Size and color may be slightly different due to manual measurement and different light conditions. Thanks for understanding. Specifications: Laser Power: 5.5W/ 10W/ 20W/ 30W/ 40W/ 80W (Optional) --Adjustable Focal Length: 5.5W/ 10W/ 20W (20-70mm) --Fixed Focal Length: 30W (12.6mm)/ 40W (40mm)/ 80W (40mm) Color: Silver Material: Aluminum Alloy + Electronic Components Wave Length: 450nm Luminous Color: Blue Operating Voltage: 12V PWM/ TTL Input: DC 3.3V-12V, 100Hz-50KHz Input Interface: XH2.54-3 Pin (+, -, PWM/ TTL) Continuous Working: Unlimited Operating Temperature: -20℃~70℃ Laser Head Size: Approx. 5.5W/ 10W: 105 * 30 * 30mm / 4.13 * 1.18 * 1.18in 20W: 120 * 40 * 40mm / 4.72 * 1.57 * 1.57in 30W (12.6mm): 115 * 40 * 40mm / 4.53 * 1.57 * 1.57in 40W (40mm): 100 * 40 * 40mm / 3.94 * 1.57 * 1.57in 80W(40mm): 125 * 47 * 44mm / 4.92 * 1.85 * 1.73in Package Size: Approx. 16 * 6 * 6cm / 6.30 * 2.36 * 2.36in Packing List: 1 * Laser Module 3 * Screw 3 * Washer 6 * Paper Card 1 * Laser Shield (Green) 1 * User Manual (English)