Abstract: A small bore tubing system employs affordance to assist distinction between different applications of medical tubing and their interconnections, as well as unique keying to avoid misconnection between tubing of different applications. Said affordance is by shape of a grip on connectors of the system, which shapes provide both visual and tactile application-specific affordance (eg. spine and ribs to indicate neuraxial application). Further mechanism affordance ensures appropriate connection mechanism is employed. A kit of components of a medical small-bore tubing connection system has a first converter (14), a second converter (30), a syringe (10) and a needle (50). Each converter (14, 30) has a through bore, a standard female (16) and male (36) connector, and a “different” male (18) and female (32) connector element. The first converter (14) has a latching mechanism (control ring) (20) on the different male connector (18) and which is adapted to engage a flange (34) of the corresponding female connector.