This is the Thunder Tiger RL-53H Redline Helicopter Engine. The Redline brand is a range of products from Thunder Tiger focused on High Performance and Power! This series of engines features high performance and extreme power surpassing the competition! Equipped with the largest displacement and incredible power, the RL-53H is the best choice nitro power plant for your 50 size helicopter.
This engine weighs less than the popular O.S. 50 Hyper helicopter engine, yet produces more power! So install the Thunder Tiger RL-53H in your helicopter, and get the extreme power you always wanted!