A mechanical face seal for providing a seal between a shaft (11) and a housing (16) includes a first seal face member (10) mounted on the shaft (11) in fixed rotational and axial relationship and sealed with respect thereto and a second seal face member (15) mounted in fixed rotational relationship but moveable axially of the housing (16); said second seal face member (15) being sealed with respect to the housing (16) by means of a sealing element (28), the sealing element (28) being located in a groove (25) defined between opposed surfaces (27, 26) of the second seal face member (15) and housing (16), the wall of the groove (25) between the sealing element (28) and the side of the seal exposed to a product being defined by a friction insert (35) slidably mounted on the second seal face member (15) and providing a close clearance (30) with the housing (16).