Between an untapped customer base, healthy vitals, and a massive international opportunity, rapid manufacturer Proto Labs (NYSE:PRLB) makes a strong case to be bought today.

Worldwide, there are hundreds of thousands, if not millions of potential product developers that could benefit from Proto Labs' rapid injection molding and CNC machining services. Considering the company served less than 7,300 product developers last quarter, there's still plenty of opportunity to grow its customer base over the long term. Ultimately, increasing awareness of its services will play a key role in driving customer growth.

As far as vitals are concerned, Proto Labs grew its product developer base by 21% year over year in the fourth quarter, while spending per customer increased by an astounding 9%. From an investor perspective, this shows how Proto Labs has been successfully increasing awareness of its services and customer satisfaction remains high.

With less than 30% of Proto Labs' revenues coming from international sources, there's definitely opportunity for Proto Labs to grow its worldwide manufacturing presence in the future. Between these three factors, 3-D printing analyst Steve Heller makes the case for why you should consider buying Proto Labs today in the video below.

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