1-40PCS 20mm Deep Hole Long Nib Head Markers For Metal Perforating Pen Waterproof Bathroom Woodworking Decoration Multi-Purpose Features Versatile Combo Set 8 pro-grade markers in solid colors (Red/Blue/Black) or custom mixes (e.g., 4Red+4Blue, 3Red+3Black+2Blue, 1Red+1Black+1Blue，1Red ， 1Black ， 1Blue), perfect for high-frequency use, team workflows, or color-coded projects. ️ Deep Hole Specialist 20mm tungsten nib (0.78 inches) reaches 15mm deep holes – mark hidden joints, engine bay parts, or narrow gaps without disassembly, saving 50% time! ️ All-Weather Durability IPX5 waterproof ink resists rain and oil. Quick-dry formula (<3 sec) stays crisp on polished metal or greasy surfaces. ️ Military-Grade Build ABS shockproof body + anti-slip grip , survives -20℃~80℃ extremes. Nib lifespan: 100,000+ marks (3x longer than average). Universal Hard Surface Mastery Works on wood, concrete, tile, glass, plastic, and automotive parts. Precision <0.5mm for carpentry, metalwork, or DIY crafts. Specifications ️ Product Name : DeepReach Pro Markers (8Pcs/Set) Dimensions : 13.7cm L (5.4in/0.45ft) • 30mm nib (1.1in) • 1.5cm diameter Color Options : Solid Sets: 8Red/ 8Blue / 8Black Mixed Sets: 4Red+4Blue / 4Red+4Black / 4Blue+4Black / 3Red+3Black+2Blue/1Red+1Black+1Blue ️ Material : ABS plastic + tungsten carbide nib Applications : Hardware Marking • Wood Marking • Tile Marking • Glass Marking • Automobile Manufacturing Marking • Perforation Positioning Product List Solid Color Set : 8 markers in Red/Blue/Black， 1 markers in Red/Blue/Black Mixed Sets : 4 Red + 4 Blue 4 Red + 4 Black 4 Blue + 4 Black 3 Red + 3 Black + 2 Blue (Best Value) 1Red+1Black+1Blue Notice Size Tolerance : 1-2 cm manual measurement error possible. Color Variation : Actual colors may differ slightly due to lighting or screen displays. Real-World Use Case Auto Repair : Mark bolt specs inside 15mm engine holes with red ink – no disassembly needed! Custom Furniture : Blue markers stay put on angled surfaces (anti-slip grip) for precise mortise measurements.