We saved a ton of money by using 1.5 inch PVC schedule 80 and a couple pieces to strap metal to block dirt and small rocks from entering the bean platform. What we did on our 220 and 920 is take two 10ft sticks of 1.5 inch PVC glued them together and used five pieces of strap metal to bolt them on behind the sickle on one of the main flex platform 1_2 inch bolts The plastic pipe flexs real nice with the head and keeps just as many dirt clumps and rocks out of the header as the Johnson gaurds do.