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This year's look for the Apple Watch will be pretty much the same as last year's.

Apple's wearable won't undergo a substantial refresh of its external design until 2017, analyst Ming-Chi Kuo said in a Monday investors note snagged by blog site Apple Insider. A new version of the watch is coming in 2016, but it will sport mostly internal enhancements, according to Kuo, who said he expects to see "spec improvements with limited changes to form factor design."

Meanwhile, sales of Apple's smartwatch will tumble, Kuo said.

Launched last year, the Apple Watch quickly became the dominant player in what remains a lackluster market for smartwatches despite efforts by tech noteworthies from Apple to Samsung to Motorola, as well as traditional watchmakers including Tag Heuer. Demand for wearables has grown over the past couple of years, yet many people still don't see them as must-have items.

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Kuo didn't reveal what internal enhancements this year's second-generation Apple Watch would offer.

Previous speculation has focused on changes that include better battery life, the addition of a camera and less reliance on a link with an iPhone. Kuo said he expects mass-production of the next Apple Watch to start in the third quarter, according to 9to5Mac. That means we'd likely see the new edition debut in September when Apple unveils its next iPhone.

As for Apple Watch sales, Kuo struck a note of pessimism.

The analyst said he believes shipments of the watch will drop by 25 percent this year to 7.5 million units, down from an estimated 10.6 million last year. Kuo blamed the dour forecast on several factors, including the immaturity of the smartwatch market, the lack of killer Apple Watch apps, limited battery life and the dependence on the iPhone for many of the watch's features.

Forecasting remains an inexact science, but Kuo has a solid track record at anticipating changes to Apple products.

Apple did not immediately respond to CNET's request for comment.