The G4M was designed for long range and high-speed operations. Consequently, weight saving measures were incorporated such as dispensing with self sealing fuel tanks, which caused Allied fighter pilots to give it the derisive nicknames "one-shot lighter", "flying Zippo" and "flying cigar". Similarly, the Japanese Navy called the G4M the "Type One Lighter" and "Hamaki" ("Cigar"). This was due to the fact that on many occasions, it was used for low-altitude torpedo attacks where its performance advantages were negated.
Using its long range and high speed, the G4M could appear from any direction, and then be gone before many fighters could intercept them. The 20 mm cannon in the tail turret was much heavier armament than commonly installed in bombers, making dead astern attacks very dangerous. Near the end of the war, the Betty was used as a common kamikaze-carrying and launching platform, and was the usual aircraft for carrying the Ohka kamikaze rocket aircraft.
Armament included a dorsal turret featuring a 20 mm cannon; 2 20 mm Type 99 cannon; tail turret, top turret, 4 7.7 mm Type 92 machine gun; nose, waist, cockpit . The G4M2 carried bombs; 1 1,055 kg (2,326 lb) Type 91 Kai-7 (improved model 7) aerial torpedo bomb or 1 ? 800 kg (1,760 lb) bomb or 2 500 kg (1,100 lb) bombs or 1 Type 3 - 800 kg (1,760 lb) no.31 ray-detective type bomb + 12 60 kg (130 lb) bombs.