Seems to be friction. He uses haki to coat his arms, and when his arm goes through high speed, the friction between his haki coated arms and the air causes it to ignite.
In many episode we seen luffy using fire power in his move but everyone is saying that it was only speed or haki but my opinion is luffy will use fire power in war with kaido to finish him. Luffy is also unknown to ace fire power just like haki before timeskip in onepiecs.
Gum Gum Red Hawk Very possibly, it is the friction of air against the gum-like composition of his fist, combined with the speed of stretching his flexible arm, which results in Luffy's arm igniting into flames to hit his enemies with a hardened, flaming punch.
"Luffy's Full-Power Blow! Red Hawk Explodes" is the 565th episode of the One Piece anime.
After entering Gear Second, Luffy uses Busoshoku Haki to harden his arm entering in Gear Second Busō. He then stretches it back like Gomu Gomu no Bullet. When cocked back, his arm ignites, releasing a stream of fire. When the attack hits, it creates a fiery explosion even underwater and deals immense damage.
1 Monkey D. He has got some terrific powers up his sleeve, such as his Gears, which give him access to some of the Six Powers as well. Using Gear Second, Luffy gains the ability to use Soru and move at blinding speeds, overwhelming even a Six Powers master in doing so.
According to BlockToro, it has been known that Luffy is immune to lightning, as seen in the Skypiea arc. Luffy may be using a Haki to diffuse Kaido's Bolo Breath. It's also possible that the Beast Pirates' ability is lightning and not a fire. If it's true, being a rubber makes Luffy immune to their attacks.
Nope, he is immune to certain attacks such as bullets, but it has been shown early on in the series, that people with enough strength can infact hurt him just by punching, without using Haki. Yes and no Luffy is not immune to swords, spears, etc.
The Straw Hat Pirates head revealed it's because he's made of rubber. Luffy may be using a Haki to diffuse Kaido's Bolo Breath. It's also possible that the Beast Pirates' ability is lightning and not a fire. If it's true, being a rubber makes Luffy immune to their attacks.
How many towels do you need in your bathroom? In a normal week, most families will use about two sets of towels per person, with each set consisting of a bath towel, a hand towel and a washcloth.
The grand total of towels needed for a family of four is eight bath towels, twelve hand towels, and 28 washcloths. For guest towels , add four bath and four hand towels per person, plus 14 washcloths (if you're hosting for a week).
There's no hard and fast rule here, but to get that fluffy feeling when you step out of the shower, you'll want to replace your bath towels when they lose their absorbency — which experts say is about every two years.