The Thunderheads are legendary. Chances if you don't have any then your father or grandfather does because the NAP Thunderhead used to be one of the only accessibly fixed blade on the market for years until other brands came up with their own flashy ideas, but the Thunderhead excels in every department. One of the key components that keep the Thunderhead above others is the patented micro groove Slimline ferrule. This grooves improve flight accuracy and penetration making no other broadhead fly as true as the Thunderhead. Period.