Best purchase I've made to make a broke down 3900 brand new again. Needed a new drive unit for it but would cost 136 at store or 109 on line. Buying this part for 139 was the best deal cause it replaces all the mechanical components an basically makes it brand new . Works just like it just for a new one.

Came on time. Great way to keep my pool cleaner working without investing a ton of money in a new one. Definately the way to go if you can.