Very nice M21 Muncie one groove aluminum 2 speed oval track transmission . only 3 races since rebuild . very hi-quality machine work only weighs 50lbs. great tranny for OEM trans. rules ,half the weight of a 3 spd. Saginaw. 10 spline input shaft. race ready.......these sell now for $1000.00 ...asking $650.00 (724)880-4580 Dave or ds_baird90@yahoo.com or PM me here.