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Coats & Jackets

Every part of a blazer explained

Every part of a blazer explained

A blazer is a deceptively complicated piece of clothing. You’ve probably got a couple in your wardrobe and, besides the colour and fabric, they might appear fairly interchangeable. But a blazer is made up of a host of distinct elements, each of which denotes a certain style and works best in a certain look.

“Making sure you nail things like fit and colour are essential,” says Thread stylist Alice Watt. “But if you can master the little details too, that’s what puts your style in another league.” Below, she breaks down the key elements of any blazer and the best way to wear them.

1. Shoulder

Blazer shoulder

“A blazer’s shoulder defines its shape and how well it fits,” says Alice. They come in two types – ‘structured’ and ‘unstructured’. “Structured shoulders have a piece of padding beneath the fabric, which creates a stronger shoulder line and gives a blazer more shape. An unstructured shoulder ditches the padding, so the fabric follows your body.”

Unstructured blazers tend to be more comfortable but also more casual – a blazer that wears more like a cardigan. Padding immediately makes a jacket feel more formal, but too much can start to look like fancy dress. “They were popular with bankers in the 1980s and gangsters in the 1930s.” says Alice. “Better is when it adds to your actual shoulder shape, rather than masks it completely.”

2. Lapel

Blazer lapel

The lapel is the strip of fabric that runs from the collar down to the buttons and folds across your chest. There are two elements to be aware of – the width and the style. “Lapel widths tend to vary with fashion trends,” says Alice. “In the 1980s, they were huge; through the 2000s, they were incredibly skinny. Going for either can look good for a while, but they date quickly. It’s better to stick to mid-size lapels, which reach around a third of the way across your chest at the widest part.”

That widest part is known as either a notch, or a peak. “A peak lapel looks like half an arrowhead,” says Alice, “with a point that sticks up where the lapel meets the collar. It’s a more formal style that’s more for business suits than a blazer.” Better is a notch lapel, which has a triangular gap between lapel and collar. “They’re still smart, but not quite so formal. Which makes them much more versatile.”

3. Buttons

Blazer buttons

A blazer should have between one and three buttons (any more than that and you risk looking like a Beatles cover band). “Like lapels, the middle ground is the safest,” says Alice. “Three-button blazers are preppy, so they look great with chinos and a button-down shirt. But they’re harder to dress down with jeans.”

A single-button blazer is rarer – the style is more common on slim suits and tuxedos. “It has a red carpet feel,” says Alice. “But can feel a bit showy if you wear it to lunch with your in-laws.” A two-button is more traditional and works with anything from denim to formal trousers. “Just make sure you only ever fasten the top button. The bottom button is, confusingly, just for show.”

4. Pockets

Blazer pockets

Most blazers have three outer pockets – one on each side and another at the left breast. “Some blazers have a small extra pocket – called a ticket pocket – above one of the side pockets,” says Alice. “Originally it was for storing train tickets, but now it’s mainly decorative. They make a blazer feel a touch more casual and traditional.”

Outer pockets come in three types. “Patch pockets are sewn onto the outside of your blazer, like cargo pockets on a pair of trousers,” says Alice. “And like cargo pockets, they’re the most casual. A flap pocket is smarter – it’s cut into the blazer, with a piece of fabric that covers the hole up. Most formal is the jetted pocket, which loses the flap altogether.”

The chest pocket is for a pocket square and nothing else – don’t be tempted to store your phone in there. “Ideally, you shouldn’t use any of the outside pockets,” says Alice. “If you put keys or a wallet in there then the jacket bulges and will pull out of shape. It looks messy and you can damage the fabric.” Most new blazers have the pockets sewn up – it’s best to leave them like that, so you’re not tempted to slot anything in.

5. Sleeve buttons

Blazer sleeve buttons

The smaller buttons on a blazer’s cuff are another hangover from a different era. “Back when men used to wear jackets at all times, they needed to roll the sleeves up if they were doing anything that might get their hands dirty,” says Alice. “Today, the buttons are just for show and on most blazers, they don’t actually work. Which is fine, as you’ll never use them.”

How many you have depends on how smart the jacket is. “More buttons means more formal,” says Alice. “A blazer should ideally have two or three, but if you’ve got long arms then an extra button can help your body look more balanced.”

6. Hem

Blazer hem

As with lapels, the length of a blazer ebbs and flows with fashion. “The trend recently has been for extremely short jackets that barely cover your hips,” says Alice. “Again, this will date fast. It’s also not very flattering on most men.” Instead, the hem – the bottom of the jacket material – should reach halfway down your buttocks. “It creates a better balance between your body and your legs, so you look more in proportion.”

At the back of the jacket you’ll find a slit cut into the fabric. “This is known as a vent, “ says Alice, “and it comes in two types – single or double. A single vent is cut through the centre of the hem and a double vent has a slit at either side, just behind your trouser pockets.” A single-vent blazer can work well if you want to hide your derriere, until you put your hands in your pockets and it swings open like stage curtains. “Most men look better in a double-vent,” says Alice. “It’s also much more comfortable as it won’t constrict your body when you move around.”