The John Deere AM121970 is an authentic OEM idler pulley, essential for maintaining proper belt tension and smooth operation in various John Deere lawn and garden tractors, and zero-turn mowers. Constructed from durable plastic, this pulley features an outer diameter of 114.3 mm, an inner diameter of 17.0 mm, and a width of 28.5 mm. Weighing 0.12 kg, it ensures reliable performance across compatible models.