The Expanding Shaft (OEM Part No. 3128306383) is a wear part compatible with Meishan M4C, Macheng E70, Dominican M4C, Simba E7C, M40S, Simba H1354, Simba H1254, and M4C ITH drilling rigs. Manufactured from high-strength alloy steel, it is designed for use in the drive and expansion system at the expanding shaft position. The expanding shaft ensures secure force transmission, stable mechanical expansion, and reliable alignment of connected components during drilling operations. Its durable, wear-resistant construction provides long service life, high strength, and dependable performance in demanding underground mining, tunneling, and rock drilling environments.