Product review (5 stars): Shaft/Mode Shifter Assembly with tub seal
The product was easy to install and worked great.  The item description should state that the tub seal comes with the shaft and mode shifter assembly.  I ordered a tub seal at the same time as the shaft and mode shifter assembly and now I have an extra tub seal that hopefully will never be used.  Another provider shows a picture of the product with the seal.