The 18 foot SR5400 and 20 foot SR6000 were by far the most popular models built. The machine was designed for use in both wheat and rice. The cross sectional diagram below shows that the rotor feeds the crop back onto draper belts which then feed the material back to an uncovered auger.
The SR was a very successful model and most of the original machines are still in the field today. A strong demand for a wider machine as well as customer concerns over the durability of the draper belts (mostly due to rodent damage incurred over the winter) meant that the SR range was discontinued in 1994.