Huawei launched the Ascend P1 and P1 S smartphones at CES 2012 on Monday, part of the Chinese telecoms company's drive to make its devices more of a household name.
The handsets will go on sale in Europe, the US, Asia-Pacific countries and Australia.
They have the same hardware configuration, meaning they will arrive with a dual-core 1.5GHz TI OMAP 4460 Cortex-A9 processor, Android 4.0 Ice Cream Sandwich operating system and a 4.3-inch Super-AMOLED Corning Gorilla Glass display.
There is almost no difference between the P1 and P1 S, aside from thickness of chassis. The P1 S measures 6.68mm, whereas the P1 is 7.69mm. That makes the P1 S (shown above) the slimmest smartphone on the market, according to Huawei.
"The Ascend P1 S demonstrates our on-going commitment to innovating high-quality devices that utilise the latest hardware and software technologies," Richard Yu, chairman of Huawei Device, said in a statement.
In limited hands-on testing, ZDNet UK found that while the P1 S's display is vibrant, it seemed to be less responsive than the display found on other handsets, such as the Nokia Lumia 800. It also showed minor signs of lag on one occasion.
In addition to the difference in thickness, additional camera software comes pre-loaded on the Ascend P1 S (shown here in side view).
At the outset, Huawei essentially did not plan to produce the slimmer of the two models, a spokeswoman for the manufacturer told ZDNet UK.
"Consumers in the Asian market demand that phones are as thin as possible. When the engineers finished making the P1, they thought, 'How can we make this design more efficient?'" she said. "The 'S' stands for slim."
Most of the reduction in depth came from discovering a new way of making the glass display thinner, according to Huawei.
Both smartphones have an 8-megapixel camera with 1080p HD video-capture capability, along with a 1.3-megapixel forward facing camera for video calls.
Pricing has not yet been announced, but ZDNet UK understands the Ascend P1 S is expected to launch with a sub-$400 (£261) price tag. Their official launch is scheduled for April, but a spokesman said the Ascend P1 could make it to market a little quicker, around March.
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