Replacement 1-3/4" X 20 Spline Hub for FD4 Clutch. The FD4 is a 4 friction disc slip clutch. Can be used on over 10 Land Pride Models as listed below as well as many PTO's from other manufacturers. Clutch hub has flange and is made by Eurocardan. Fits Models: Land Pride- RCR3596 Land Pride- RCR3596 Land Pride-RCR3510 Land Pride- RCR3510 Land Pride- RCR2596 Land Pride- RCR2596 Land Pride- RCR2510 Land Pride- RCR2510 Land Pride- RCF3696 Land Pride- RCF3610 Land Pride- RCF3096 Land Pride- RCF3010 If you are not sure if this unit will fit your mower please contact us and we will be glad to help make sure this will fit.