Four major seriesGeared motorSelected manual downloads. Germany's boserl production has four series ofreducing machines, namely, r series and axle slash-reducing motors, f series parallel axle slash-reducing motors, k series and k series slash-reducing gear gears, and s series s series slash-retard snails. The following is a sample of the k-series propeller gear-reducing machine, for which three other series of selected types are required, with a micro-credit on the website. thank you for reading this article