A connection apparatus includes a male plug which may be mated into bayonet-type engagement with a female socket. The plug has at least one radially projecting lug and the socket has at least one axially extending insertion channel and at least one adjoining locking channel within which the lug may be received. The locking channel includes at least one depression which is located radially angularly offset from the insertion channel. Engagement between the lug with the depression resists unintentional detachment of the connection.