Lawn Boy Drive Roller part# 605827 is 2-5/8" long and has an outside diameter of 7/8". This is the right hand drive roller for the following lawnmower models; 8226, 8227, 8227E, 8228, 8229, 8229B, 8229E, and 8229S. There may be models that use this part that we do not have listed here. Please refer to your owners manual or a parts breakdown for your model, to assure that this is the correct part for your machine, before you order.