Clip to stop Z axis linear rods rotating on Sintron Prusa i3

I mounted the z axis limit switches on the z axis linear rods. This works ok except for the fact that the rods can rotate, moving the limit switches and stuffing up their calibration and triggering. This clip bolts on to the holes in the top support for the z axis linear rods. I think these holes were meant to have plates screwed over them to stop the rods falling out, but I never got around to it. As well as stopping the rods turning, this clips also stops the rod falling out.

All screws and