The Husqvarna 505891640 is a genuine X-Force 10-inch (254mm) guide bar, engineered for optimal performance and durability on Husqvarna chainsaws. It features a 3/8 inch mini pitch and a 1.3mm (0.050 inch) gauge, along with an A041 bar mount and 40 drive links. Its smooth profile and unique nose design reduce kickback and ensure efficient cutting. This guide bar is compatible with a wide range of Husqvarna chainsaw models including the 120 Mark II, 130, 235, 240, 435, 440, 440e, 445, 445e, 450, 450e, 543 XP, 545 Mark II, 550 XP Mark II, T435, T540 XP Mark III, 525P4S, and 525PT5S.