persons skilled in the art will understand that fluid flow to ports 16 can be effected or facilitated in a variety of other ways by way of non limiting alternative example upper seal ring 60 could be made to fit fairly closely around mandrel 10 while including one or more longitudinal grooves or channels allowing flow through seal ring 60 lower seal ring 50 may be non rotatably secured to mandrel 10 by any suitable means such as to provide one non limiting example by way of an interference fit at a cylindrical interface 52 with mandrel 10 as shown in fig2 similarly bearing assemblies in accordance with the present disclosure are not limited or restricted to any particular means for non rotatably securing floating upper seal ring 60 to housing 20 or for permitting longitudinal movement of upper seal ring 60 relative to housing 20 however fig2 illustrates one non limiting example of means for providing these features in the illustrated embodiment upper seal ring 60 is formed with one or more axially oriented splines 62 slidable within mating grooves 25 formed in housing 20 during operation of a mud motor incorporating bearing assembly 100 mandrel 10 will rotate relative to housing 20 so lower seal ring 50 will rotate relative to floating upper seal ring 60 in the typical case there will be limited axial travel between mandrel 10 and housing 20 as the configuration of bearing assembly 100 changes from on bottom to off bottom loading conditions or vice versa fig2 illustrates the operational case in which bearing assembly.