It’s easy to master this spring’s hottest trend — here are the 4 pieces you need to buy

Getty/John Phillips and Getty/Anthony Harvey

There's no doubt about it: military style is in.

Heavy wool great coats, fishtail parkas, thinner bomber jackets, and four-pocket fatigue coats are everywhere these days. It's even infiltrated color palettes, and we see a lot more muted navys, olives, and beiges on the runway. The trend is transcending seasons and even gender boundaries.

If you need proof, look no further than the US Department of Defense contractor Alpha Industries, who claims a 30% increase in revenue for 2015, according to Esquire. Alpha makes a large number of authentic military-inspired garments, including the now super-hot bomber jacket.

In the most recent men's fashion week, which highlighted styles for fall and winter of 2016, a number of designers — including Burberry, Balmain, and Dries Van Noten — showed off heavily military-inspired looks.

The best part about this trend? Military style is incredibly easy to wear and is already quite pervasive in popular wear. (For example, the modern peacoat is derived from a naval style that was used to keep sailors warm.)

Here's how to rock it:

Field Jacket

The field jacket is a four-pocket jacket style that is the civilian equivalent to the fatigue jacket.

It usually comes in olive and navy, and it's a great casual alternative to the dressier trench coat. 

Slap it on over a chambray or Oxford shirt, and you've got a perfect Saturday outfit.

Pictured to the right is J. Crew's take on the field jacket in olive. ($198)

Bomber Jacket

We've already told you that the bomber jacket is the one you need for spring.

We love its silhouette and casual style. Put them on over a t-shirt or button-up shirt for a super-easy casual look.

Pictured to the right is Alpha Industries' authentic model, known as the MA-1 Flight Jacket in 'stratos' ($135).

Great Coat

The great coat is the overcoat's military-inspired cousin, and the two share a similar DNA.

The great coat is different, however, with its larger collar, button stance, and double-breasted style. It's also thicker, less fitted, and often comes in military-inspired colors like olive.

Look for them to take the world by storm next fall and winter, where they'll be a fine stand-in for many men's overcoats.

This model pictured was included in J. Crew’s Fall/Winter 2016 presentation, and will hit stores later this year.