Abstract: A seal between a housing and a rotatable shaft is provided, comprising a first ring member generally concentric with a rotatable shaft, the first ring member being attachable to the shaft in a non-rotatable position relative to the shaft, the first ring member further having an annular self-lubricating sealing surface facing away from the first ring member; and wherein the sealing surface is adapted to face a fixed annular surface and to slidably and sealingly engage the fixed annular surface when the first ring member is biased toward the fixed surface. The self-lubricating surface may be provided on a sealing ring which is biased against the fixed surface. The self-lubricating surface, sealing ring and/or first ring member may be constructed of a fluoroplastic material such as glass filled polytetrafluoroethylene. The fixed surface may be provided on a second ring member, enabling the seal to function as a cartridge unit.