Hot Rod head inspred by G1 cartoon and IDW "All Hail Megatron" series. The head has a 4mm ball joint socket and is designed to fit onto Combiner Wars Stunticon cars. While I tested it successfully with WSF, FUD is high recommended.
Note that, due to the small cavity under the hood of Breakdown figure specifically, some cutting is required on the figure for the head to fit. I recommend removing half of the 5mm stalk that is used to hold the gestalt hand/foot accessory under the hood.