#25S-E. 5R110 4-Pinion OD Planetary Housing. Made from 4140 HTSR billet steel for high horsepower and EXTREME use. No more exploding planets or spline failure. 4 pinion planet for early 5R110 applications with 94 tooth overdrive ring gear. Includes assembly pin to make needle bearing installation easy. Pinion staking pins supplied, no welding required to retain pinion pin.