A pneumatic multi-way connector has a cycling motor 1 and a cycling valve 2 for cycling pressure air from a non-shown pump to selected ducts 31, 32, 33, 34 in an outlet socket 3. The ducts are complementary to inlet ducts 41, 42, 43, 44 of an inlet plug 5. A ring cover encloses a rigid ring 16 which has a button 17 exposed at a top portion cover. A spring 18 biases the ring and the button upwards. The ring cover and the ring have a central opening 19 for receiving the disc 52 and the nose 55 of the cover 50 with the slots 56,57 aligned with the tabs 11,15. The plug is located radially around a peripheral engagement region 20 of the opening 19. The disc 52 has an upper latch lug 58, which engages behind a rib 59 integral with the plate 14. This is at the top of the peripheral engagement region 20. At the bottom of the zone, the disc has a lower latch lug 60, provided in two parts separated by the slot 56. This engages behind the bottom sector 61 of the ring 16. The ducts 31-34 are provided in a resilient member 35 captivated between the outlet plate 14 and a stator moulding 36 forming part of the cycling valve, which does not form part of the present invention and will not be further described save that it has a rotor 37 on the side of the stator remote from the resilient member. The bores terminate at the tubes 38 having deformable noses 39. These abut the disc 52 and form a seal therewith. Release of the plug, by depression of the button 17, allows the tubes and noses to recover, pushing the plug out to a position whence it falls down, this being the intention in the event of an emergency calling for disconnection and deflation of the mattress.