【DIMENSIONS】 - Thread Diameter 0.171\ - Head Diameter 0.55\ - Length 3\ - Use with T30 Star Bit.,【PREMIUM QUALITU】 - These Heavy-Duty wood screws are made of high-quality alloy steel, offering strength and durability, They're capable of withstanding considerable weight and pressure without bending, rusting, or breaking, making them ideal for heavy duty applications. These screws passed the 1200 Hour Salt Spray Test without coating failures. it remain smooth and fully functional even after prolonged exposure to the elements; They can endure and resist the rusting effect of sun and rain.,【KNURL THREAD & SELF-TAPPING】 - The knurled shank significantly reduce drill torque requirements, and the deep, sharp threads allow easy drilling into the wood without damage. The extra sharp point makes screwing a breeze, reducing the need for pre-drilling and saving you time and effort.,【MODIFIED TRUSS WASHER HEAD & STAR DRIVE】The modified truss washer head design of our structural lag screw guarantees a flush and neat finish, enhancing the overall appearance of your woodworking creations. Featuring a T30 star drive style, these wood screws ensure a safe and efficient fastening process without slipping.,【APPLICATION】 - These heavy duty screws can widely use for outdoor, home and industrial applications such as deck building, log construction and timber framing.