Gottlieb's Knock Out woodrail is a beautiful game.
A V-shaped mechanism prevents your ball from draining until you complete certain goals.  
Your main goal is to knock down a mannikin boxer in a three dimensional boxing ring in the upper middle of the playfield!  You do this by hitting the 5 bumpers, the rollovers, or the center target.
The 5" bell when you knock down your opponent is great fun!