(Pocket-lint) - Even Pebble couldn’t have guessed that its Pebble Time smartwatch would have such phenomenal success on Kickstarter as it did, making more than $12 million in funding already – a million of that in just 30 minutes. But it will be hoping to replicate that feat with a speedy follow-up, as it has announced the Pebble Time Steel, which will also be available first on the crowd funding site.

Like it did with its original Pebble smartwatch, the company has expanded its line-up with a Steel edition of the latest model. And what’s more, the Pebble Time Steel adds extended battery life, promising up to 10 days of lifetime on a single charge.

It has the same full colour e-paper display of the conventional Pebble Time, plus the built-in microphone and waterproofing the previously announced smartwatch sports. But build materials are more premium, with silver, black and gold finishes.

READ: Pebble Time: Hands-on with the most successful Kickstarter project ever

It is the same dimensions as the Pebble Time, but the Steel edition is around one millimetre thicker to accommodate the larger battery. It also now comes with a Smartstrap (in fact, two in the box; stainless steel and leather) that third-party sensors can be attached to.

Pocket-lint was told by Pebble founder Eric Migicovsky that could include a GPS sensor for runners or navigation, a heart rate sensor, NFC add-on for contactless payment or anything else developers might devise. It’s a way of customising the watch to do the things you most want.

READ: Pebble Time: What is it and what's new?

A Smartstrap will also be shipped with the Pebble Time and because of a quick release mechanism, the straps can be changed “in a matter of seconds” so you can have different sensors attached to different straps for a variety of tasks.

Pebble Time Steel will start to ship in July and like the Pebble Time, early backers will be able to buy one at a discount on its dedicated Kickstarter page. It costs $250 (£162) through Kickstarter, with a final retail price of $299 being adopted later down the line.

And Pebble hasn’t pulled a fast one on the dedicated fans who backed the Pebble Time just a week ago. Any Kickstarter backer of that device can upgrade if they want, without losing their place in the shipping queue.

We have to say we like the feel of the new Pebble Time Steel, perhaps more than the conventional one. You could say that Pebble has another hit on its hands. Or wrists.

Writing by Stuart Miles.