"It is a DY S4500 and I bought it in a yard sale to resell. I broke a belt on my Craftsman DGT 6000 and decided to just finish up with my resell tractor. I was amazed how quick it turned and the steering was so much easier than my bigger mower, I just decided to keep it. I love how easy the deck comes off. I had trouble with the drive belt coming off and discovered a keeper (190) part no. 194318, from the v-pulley at the back of the brake arm was broken off. The exploded view of this thin plate in the parts manual is difficult to make out, but it has a leg that sticks down to keep the belt on. It must be there or your belt comes off. Put a new one on and it is a great mower."