Product review (5 stars): Works well; however, it was not the same ...
Works well; however, it was not the same length as the original - a little shorter, but does not affect the function of it.  I centered the two reference dots with the center of the tub top and followed each size down, stuffing the gasket into its seat.  The left side met up flesh with the bottom while the right side was about 3/4 in too long.  For reference, the old one had both sides ~ 1 inch too long, which trapped all kinds of nasty junk.