Missing from the SkyNews picture are a few elements. It would also need a power source, and either an altitude device or countdown timer or possibly a mobile phone trigger, for remote detonation.
It could of course just be a media mock up but the size is about right for this type of improvised device.
It shows a soft drink can and what appears to be a detonator and switch on a blue background.
The Metrojet plane crashed in Egypt's Sinai Peninsula last month, killing all 224 people on board.
Sky's Foreign Affairs Editor Sam Kiley said at first glance the image does appear to show a detonator.
He said: "But that means it would have to have been triggered by a live person and the bomb was in the hold.
"And it would have shown up even on an egyptian scanner if it was carried by a passenger.
IS claimed it exploited a loophole at Sharm el Sheikh airport, where the jet took off from, in ordered to smuggle a bomb on board.
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