30 cm Sägenspezi guide rail drive 1/4 inch 64TG 1.1 mm suitable for Stihl MS151. The guide rail only fits in conjunction with Sägenspezi chains, or standard 1/4 inch 1.1 mm chains. We are happy to recommend our sword sets: 56149AR0181X 56150AR0182X. This guide rail is durable and of high quality. The rails have a roller star.