Abstract: A gear type flexible shaft coupling made up of identical halves each including an externally toothed hub surrounded by an internally toothed sleeve in meshing engagement therewith, sleeve connecting flanges with fasteners threaded alternately from opposite sides of the sleeves, an aligning ring extending between the facing sleeves to radially align the sleeves, an axially outer flexible metallic seal ring assembly between the hub and sleeve, a portion of such sealing ring assembly being abuttable against a shoulder on the hub to maintain a substantially uniform lubricant reservoir within the coupling half, an axially inner non-metalic removable sealing cup closing the inner end of the sleeve forming a closed lubricant chamber in each half, such cup including a detent to maintain the cup in position when the coupling halves are disassembled, and elastomeric, axially-spaced sealing rings in the tapered bores of the hubs to facilitate removal of the hubs from the shaft.