(Pocket-lint) - Acer has lifted the lid on the Swift 5, shown off earlier this year as the “lightest 15-inch laptop in the world”, and tweaked Swift 3 models.

Today’s highlight is the 15-inch Acer Swift 5. Acer has already announced this model, but we knew almost nothing about it bar its sub-1kg weight.

The 15-inch Swift 5 weighs 990g — hurrah — but also has one of Intel’s brand new Whiskey Lake processors. Either a i7-8565U or Core i5-8265U.

Acer says the battery lasts up to 10 hours, not bad for a model this slim. But it’s still 15.9mm thick, which you may not expect from one of the lightest big-screen laptops ever.

Magnesium is the key to its low weight. The Swift 5’s top and bottom are made of a magnesium-lituhim alloy, the inside magnesium-aluminium for a slightly more metallic feel. If you hadn’t guessed, magnesium is light among metals.

Other Swift 5 specs are sensible, and ordinary. You get a 1080p IPS touchscreen display, up to 16GB RAM and 1TB SSD storage, two normal USBs, one Gen 2 USB-C and an HDMI.

The 15-inch Swift 5 starts at 1099 Euro, likely a similar figure in pounds, and will be available from November.

Acer has also tweaked the 14-inch version of the Swift 5, which weighs 970g. Like the 15-inch laptop, it will be available with Intel Core i7-8565U and i5-8265U CPUs, from September. Prices start at 999 Euro.

The Acer Swift 3 line gets similar treatment.

There are no superlatives here. The Swift 3s aren’t the thinnest, the lightest, they don’t use the most spangly materials.

However, they are often a great choice for average buyers. Again, they will soon be available with Intel Whiskey lake CPUs, this time including the lower-end Intel Core i3-8145U.

There are 13-inch and 14-inch models, and the larger comes with the option of discrete GeForce MX150 graphics. However, it’s the 13-inch Swift 3 that also comes in a 4G variant, the Swift 3 SF313-515.

As ever with Acer’s ultra-mainstream laptops, we’ll have to see which exact specs make it to UK retailers. However, Acer says prices will start at 799 Euro for both the 13-inch and 14-inch Swift 3s. And the first models go on sale in October.

Writing by Andrew Williams.