This german "Molotov" was factory made of green glass, in the same size as a normal wine bottle. It was filled with an oil-petrol mixture and closed by a cork. The bottle had 2 cavities on the side which held 2 fuzes. So far I have seen 2 possible fuzes, the pull fuze for the stickgrenade and a plastic(rubber) fuze which had to be lit like a match. The fuzes were fixed with a paper tape around the middle of the bottle.
After throwing, the bottle would break and the liquid mixture was ignited by the fuzes.
Two sizes are known, see photo on the right.

Above: Rubber/plastic igniter as used on the German incendiary bottle. It has a matchhead compound.

Right and below: The wooden case in which these bottles were packed and a detail of the paper label on the box.
Photos thanks to Dr. Ruby.

The photos on the right and below © Marcin.

This is how some have looked like.
The text "Feuergefährlich" was not mentioned on every bottle.
On this one, the matchhead fuze was not made of rubber like the one shown above, but made of rolled paper.