the trouble with hdmi clamps or whatever is imagine this situation..
small camera mounted on car bonnet (hood)
hdmi to monitor to agree composition with director
unplug hdmi
car drives off and plays the scene
return
plug in hdmi
watch playback
repeat
here is hdmi is being continually plugged/unplugged and clamp would not work
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my pi boards have micro hdmi and it is perfect on a computer the size of a bank card.
Some get a very short male hdmi to female hdmi connector and clamp that to the camera saving the camera port from being overused and connection / disconnection is fast and easy.