G1 Victory Deathcobra head for Combiner Wars Vortex. Due to the shape of the head it is very difficult to fit the head in alt mode. If you turn the head about 45 degrees to one side then it will fit but there might be some scraping. See pictures for details.
The head comes in two sizes.
Medium - for Deluxe figures
Large - for Weijiang Oversized KO figures