Bot both sets of roller bearings, lower ones on the appliance and the set on the trash can that rolls out. I just followed the instructions that were in the roller bearing package and only needed the tools that are recommended. Was a little tricky with the nuts, really need a person with "small" fingers to reassemble the nuts back on the lower set of bearing that are on the appliance. All in All, went well and works. Found that the new bearings are v. tight on the machine, being new, so, use lots of silicone spray after vacuuming and cleaning the rails. Took about 30 mins.