The STIHL 95129333150 is a genuine OEM retaining ring, also known as a circlip, designed for secure fastening on 12mm shafts. This KR-12X1.6 specification indicates a nominal shaft diameter of 12mm and a ring thickness of 1.6mm. Manufactured from durable spring steel, it ensures reliable performance in a wide range of STIHL equipment, including popular chainsaw models like the MS 170, MS 180, and MS 250, as well as trimmers such as the FS 55 and FS 94, and blowers like the BG 56 and BR 600. This critical component helps maintain the proper assembly and function of internal machinery parts.