The 76A/A+/C models have a snow protection kit available as a add on option. You can fly without it IFR - just not in snow. Its to stop snow accumulating around the engine inlet area - a slug of snow breaking loose without the kit can have the unfortunate result of putting the fire out. Know of it happening to a 206 with fatal results. Also has a mod so you can select continuous ignition. What was involved with the 76C++ certification I have no idea.