The John Deere M157101 Idler Arm is a genuine OEM replacement part designed for various John Deere ZTrak Mowers. This essential component helps maintain proper belt tension and alignment, contributing to the efficient and reliable operation of your mowing equipment. Engineered to John Deere's rigorous standards, it ensures optimal performance and longevity for models including Z810A, Z820A, Z830A, Z840A, Z850A, Z860A, Z910A, Z920A, Z925A, Z930A, Z950A, Z960A, Z970A, Z997R, Z915B, Z920M, Z920R, Z925M, Z925R, Z930M, Z930R, Z950M, Z950R, Z960M, Z960R, Z970R, and Z994R.