A mechanical seal comprising; a. a sleeve which is for sealing engagement with a rotating shaft; b. one or more primary or secondary sealing faces urged toward one another via a plurality of spring members; c. a gland which is for detachable attachment to a housing of within which the seal is to be situated: d. a clamp ring wherein set screws reside to provide drive between said sleeve, clamp ring and shaft; and e. one or more setting members which are detachably attached to said clamping ring to restrict axial movement and make the internal dimensions independent of tolerances and assembly accuracy.