The Hobsons X9 Class 3 Countersunk Square Timber Screw (#10-8 x 150mm) is a premium self-embedding fastener designed for fixing timber, chipboard and treated pine in general construction applications. Featuring a countersunk square drive head, it provides a clean, flush finish while delivering excellent drive engagement and reduced cam-out during installation. The Class 3 corrosion-resistant coating ensures dependable performance in indoor and protected outdoor environments, while the self-embedding design eliminates the need for pre-countersinking in most timber applications. Designed for use with an **SQ2 Square drive bit**, it is supplied in a convenient **250-piece box** and is ideal for professional trades and DIY projects alike.