The agitator stroke on a 1-18 is only 1 7/8", but looks much bigger because of the rapid 360 PPM pulsation. The "Jet-Action" 1-18 was made from 1970-1979. I have a 1978 model which is now my favorite machine to use. The sound it makes during agitation is part of the fun--a rapid "thunk-thunk-thunk-thunk" sound, and of course you can't stop watching the action either! It also is one of the few machines that can actually wash its 18 lb. rated capacity, and cleans amazingly.