18-350mm Pipe Drill Wet 350/370mm Diamond Core Wall Floor Drill Bit Hole Saw. Construction works: Wall penetration (HVAC/electrical conduits). Refurbishment: Tile/stone cutting (recessed installations). Municipal works: Road marking installation, utility trench enlargement. Aerospace-grade alloy steel drill bit: Utilises chromium-molybdenum-vanadium alloy material with HRC62+ hardness, delivering 300% enhanced wear resistance and capable of penetrating reinforced concrete. Dual-spiral flute design: 304 stainless steel body with deep chip flutes ensures smooth, clog-free drilling in both dry and wet conditions. Diamond-Coated Technology: Nano-diamond particle coating extends service life by 5 times, suitable for granite/marble. Cooling Specifications: Dry drilling operations should not exceed 30 seconds per session; water cooling is recommended for prolonged use. Safety Warning: Wear safety goggles and dust masks; rotating the drill bit is strictly prohibited. Storage Method: Store in a dry environment, coated with rust-preventative oil. All products in our store are elaborately made. We care about our valued buyers, if you have any questions, our Customer Service staff will be very glad to help you. We try our best to reply to your emails as soon as possible, however, due to the high volume of daily incoming emails and time zone difference, we may not be able to reply to your emails immediately. Please contact me before you return it. Feedback is very important to us. For the functional products in our shop, we make sure that the functions are the same as the description. About the product colour:Because of the different light and environment when the product is photographed, In a few instances the colour of the product may have a little colour difference with the actual colour of the product, I hope you can understand.