This is a pair of quality inner flange and outer lock nut set, made of iron material, integrated molding, and precision CNC machined standard parts. Designed to help modify angle grinders from 100mm to 125mm. Compatible with 20mm and 22mm bore grinding discs.Features: Compact size, lightweight, and portable, easy to carry and store. Made of iron material with integrated molding and CNC machined construction. High hardness and toughness after heat treatment, wear-resistant for extended service life. Designed for use with 100mm angle grinder rotors. Enables modification of angle grinders from 100mm to 125mm. Supports installation of 20mm and 22mm bore grinding discs.Specifications: Name: Angle Grinder Accessory Material: Iron Item Size: 40 x 40mm (1.57 x 1.57in) Package Size: 150 x 100 x 50mm (5.91 x 3.94 x 1.97in) Package Weight: 98g (3.47oz)Packing List: 1 x Inner Flange 1 x Outer Lock Nut