A clamp to attach two ribbon cables for the Pi Camera together. The cable I had wasn't quite long enough, but I had another ribbon cable that would give it enough length. 

I laid the two ends on top of each other and used electrical tape to hold them in place, but that didn't give it a strong enough connection for a working video signal. With the clamp there to press them together the camera works reliably! Just use four M3 bolts to put them together. You might need to hold the base piece with a vice or clamp or something while screwing in the top piece.