Abstract: An air injector valve for a spa is disclosed, the valve including a body and a cap. Within the body there is a valve seat and a jumper which co-operates with the valve seat to control flow of air through the valve. The body has an externally threaded section which screws, from above, into a nut positioned below an aperture in the shell of the spa. A flange at the upper end of the body prevents the valve body passing right through the aperture in the shell. The cap can be unscrewed from the body and, once this has been removed, access to the spring and jumper from within the spa is possible. The valve body cannot fall through the aperture in the shell as it remains supported by the flange.