The Hammond 197E5 is a high-frequency reactor designed for demanding applications requiring high permeability and robust performance. Featuring a carbonyl iron powder core, it's ideal for use in circuits up to 50KHz. The reactor's rugged construction, including an aluminum base and stainless steel band, ensures durability. With an inductance of 4.0mH and a self-resonant frequency of 250.5 KHz, the 197E5 provides reliable performance in various industrial and commercial applications. It is suitable for use in power supplies, lighting ballasts, and other high-frequency circuits.