This deep hole marker designed with a 1./ 30 mm long tip, which can easily deep holes or hard-reach places, convenient to use. This long nib marker can be applied for various surfaces such as wood, metal, glass, and plastic. Using good material, this carpenter durable , has a long service life. Waterproof and quick-drying, environmentally friendly and practical, not easy to fade after washing and smearing. The firm and reliable, and it is not easy to break. The pen holder has a simple ruler, which is convenient for construction and measurement. Specification: Material: Plastic, Carbon Steel Size: approx. 138x12mm/5.43x0.47inch Color: Red, Blue, Black Package Includes: 3 Pieces Deep Hole Marker Pens : Color might be slightly different due to the color calibration of each individual monitor. Please allow slightly measuring deviation due to manual measurement.