Abstract: The present invention provides a conduit clamp comprising a pair of jaws, said jaws comprising respective, opposed recesses arranged to abut against sides of a conduit, said jaws comprising means for pivotally connecting them together at one end, one of said jaws comprising an aperture, and the other of said jaws comprising a twist lock means, such that, to close the jaws and clamp a conduit, the twist lock means is inserted in the aperture and partially rotated, means also being provided for securely attaching the clamp to a stable structure.The clamp of the present invention is particularly useful for clamping relatively small diameter conduits such as electrical conduits and hose lines to a permanent structure. It is particularly envisaged for use underwater but can be used for mining and industrial applications which are not underwater.