A support is provided for conduit held on a channel member having a C-shaped cross section with lips extending toward the back wall of the channel. The support has a base with one surface adapted to fasten to the conduit. The second surface has a twist-lock fastener that includes a first and second plate, each having a width sized to fit through the space between the lips and having a length about the same as the distance between the sides of the channel. Two V-shaped deformable members join these plates adjacent the ends on the longest side of the plates. Each V-shaped member is joined to a different plate and the bends at the juncture of the two legs of the V-shaped member abut the side walls of the channel. The bends are adjacent the ends and extend beyond the plates to wedge against the channel sides as a screw draws the plates together and moves the legs of the V shaped member toward each other.