Abstract: A drain assembly is disclosed having a drain insert member with a tube portion carrying at its upper end a flange which extends radially outwardly. A clamp ring member is adapted to overlie and be clamped onto the flange member. The flange has a plurality of post members which extend upwardly from the upper surface of the flange. The clamp ring member has a plurality of upwardly extending socket forming members each defining a socket recess open at a lower surface of the clamp ring member and adapted to receive a post member in the socket recess therein. A screw member extends downwardly through the top of the socket forming member to engage the post member and draw the clamp ring member downward onto the flange in clamping arrangement therewith. The upstanding post members and socket forming members permit the drain insert member to be made by injection moulding from a two piece mould.