Portable engrave letters machine you can see the video of the product’s operation in my website. Could be ordered 5-10 pieces every time. specification: The subject product is suitable for engraving on materials of metal , porcelain .marble and glass . Front-end of machine ,there is a Tool bit. The tool bit will be Quivered when the machine is working . is quiver ,no rotation . so it is not be used like Die grinder . The machine worked like a pen , if you engrave a word , the word is like the handwriting. Not like the print. Sometimes ,moulds can be used to make better. The top of the tool bit like the top of the needle, when it is dulled. can used “grinding machine” to make it sharp the product is very populated for its compact and portable feature , compared with same kinds other machine , low noise, low shaking . you can used it to put a mark in many hard materitals as you want, The dealers or manufactures will not be confused for retured product when their product was engraved before its shipping out the plant. Voltage: 220V Power: 25W Degree: degrees button is on the back of manhine Work process: 1. plug the power 2. select one degree by the button on the back of machine 3. put down the button in Front-end of machine. Move gently on the surface which you want engrave . Now it is working, loosen the button, it will be stop . Caution: 1. The product should not be in usage by exceeding 20 minutes in case of the coil is overheated . 2. to make sure the product is not with creepage for your safety reason. 3. put the tool bit gently on the surface which you want engrave. heavy strength maybe damaged the machine. 4. please keep this product out of children to prevent accident.