A unitary cartridge seal assembly for a high pressure liquid sealing connection between two relatively rotatable liquid passage members of a rotary nozzle or a swivel and a tool having such an assembly. The assembly comprises a thimble shaped or cylindrical housing having a flanged retainer fitting within an axial orifice to hold the components together while allowing sufficient axial movement to insure complete sealing of the respective elements. The assembly provides “drop-in” replacement of wearable parts of the rotary face seal of a high pressure water jet blasting tool.