Hookcart Engraving Name Writing Pen with Tool Nib for Jewellery and All Glass Metal Plastic Wood (Blue and White) (Free Nib) It works with wood, steel, bamboo, metal, rubber, acrylic, glass, leather, and plastic. Customize and personalize anything you want - including cups, teacups, shot glasses, jewelry, keys, keychains, bracelets, wallets, belt buckles, phone cases, sunglasses, containers, and much more... Unscrew Engraver Pen from the bottom section by turning counterclockwise. Insert the battery with (+) side facing up (AA-size). Hold Engrave-It just like a normal pen, with a thumb over the control button... Press the control button with thumb; apply slight pressure and press the tool down on the surface to be engraved; hold at a slight angle. Turn off when finished by releasing pressure from the control button.