Extension kit fits onto the base of the model 80 and/or 140, raising the base up 2-3/4″. This will allow you to run a 1-1/2″ PVC pipe (not included) from under the shower floor, on top of the sub-floor to an existing drain. The drain can be positioned so the pipe can come out from under the shower floor in one of four directions. Kit includes: (4) Extension Blocks, (1) 82.400A Drain Kit