Installation video of the Mega Fins Handguard Rail System which we expect to be available for the airsoft market through MadBull Airsoft... "The Strike Industries Mega Fins hand guard rail is an ultra light weight handguard rail with a plethora of features. Our Mega Fins rail is named after the 'fins' that surround the rifle's barrel. The purpose of these fins is to help dissipate the heat generated from the rifle barrel.