8 Inch 4-Jaw Self-Centering Lathe Chuck with 1 1/2 in-8 Threaded Backing Plate About this item Outstanding Hardness: Crafted from premium HT300 cast iron, this lathe chuck features jaws with a hardness of ?53 HRC and a scroll plate hardness of ?45 HRC. Quench-hardened for enhanced durability, it ensures excellent hardness and rust resistance, ensuring a long-lasting service life Self-Centering Function: The built-in self-centering feature allows for hassle-free use without repeated calibration. It ensures precise control over clamping accuracy, maintaining the stability and high precision of the lathe chuck for flawless performance 8-Inch 4-Jaw Lathe Chuck: Featuring a 1 1/2 in-8 threaded adapter backing plate, this lathe chuck achieves a faster and more stable connection to your machine. With a 2.56 in (65 mm) inner diameter and 8 in (200 mm) outer diameter, it clamps workpieces ranging from 0.16-7.87 in (4-200 mm), making it versatile for a variety of sizes Hassle-Free Operation: Featuring a simple, compact design, this lathe chuck balances functionality and reliability. Equipped with a T-shaped tool, installation of our lathe chuck is a breeze. Just follow the correct sequence for a seamless setup Ideal for Most Lathes: Whether you're working with metal, drilling, or milling, our lathe chuck will enhance your machining efficiency and flexibility. It helps you achieve precise and consistent results every time. Specifications:- Length: 28.0 in, Width: 28.0 in, Height: 21.5 in (description exceeds maximum possible length)