Grassflap is the most versatile and useful OCDC/chute blocker I've ever used. Takes some time to install and learn to use, but so simple and effective to use in the full open, semi closed and full closed position. Once you get the muscle memory down it is by far the best. Very strong build quality and very customizable to suit your mower deck. The team at Mowermerch are some of the best in the businesses!