Abstract: A unique laboratory glassware system is provided which includes glass functional members and an elastomeric coupling member for joining two of the functional members in axial alignment. Each of the functional members has a conduit portion terminating in a male sealing portion. The male sealing portion comprises an annular flange with a front conical surface and a rear locking shoulder. The coupling member includes a central opening having a gasket portion separating two axially aligned bores that include a female sealing portion corresponding in profile to the male sealing portion. The conduit portion of the functional members form a positive engagement with the female sealing portion of the coupling member such that the joined functional members snap into position and are locked against internal pressure that could pull them apart.