What kind of clothing was the 'MK3 flight jacket' mentioned in the jumper description originally?

A flight jacket refers to a military coat worn by fighter pilots to endure the harsh cold and wind at high altitudes. Among them, the MK3 is a representative flight suit adopted by the Royal Air Force and used as standard equipment for pilots for half a century.

The cockpit is cramped. The key features of this clothing were keeping the length short so it wouldn't get caught on the instrument panel, and firmly wrapping the closure and collar to keep the wind out. EASTLOGUE's women's down jumper is a piece that takes the original form of this MK3 and reinterprets it as winter wear suitable for daily life^[1].

Functional elements of flight suits are blended throughout. The front panel adds military slot buttons secured with flat tape and a placket over a two-way zipper that opens from top to bottom, blocking cold air in layers^[2]. A diagonal welt pocket secured with a zipper is placed on the left waist so that belongings do not fall out^[3].

A detachable hood attached with snap buttons is hidden inside the collar^[4]. On windy days, you can take out the hood to cover your head, and usually, you can remove the hood to keep the neat collar shape of the original flight jacket^[5].

hmmm, without stripping away the practical devices born from harsh battlefields, it has naturally converted them into everyday usefulness that blocks the winter wind.