The Shims (OEM Part No. 3128318093) are spare parts compatible with 235 rock bolting rigs, Boltec-MC, and Boomer-MD underground drilling machines. Manufactured from durable alloy steel, they are categorized as mechanical components used in the equipment alignment and clearance adjustment system at the shim installation position. These precision adjustment parts are designed to maintain proper spacing, alignment, and fitting accuracy between mechanical assemblies. By providing reliable positioning support and reducing assembly tolerance issues, the shims help improve equipment stability, minimize component wear, and ensure efficient operation of mining drilling and bolting systems.