Filtronic (LSE: FTC) is a small-cap stock that I wish had been on my radar early in 2024. Just one year ago, it was a penny share trading for 22p. But after a meteoric 359% rise in 12 months, the share price has jumped to 101p.

Over five years, shares of the electronic components specialist are up a mind-boggling 839%! And they rose 12% yesterday (13 January).

Clearly, I’ve already missed out on some juicy gains. But the AIM-listed firm still has a modest £218m market cap and is growing strongly due to a lucrative relationship with rocket pioneer SpaceX.

So, could this one be a millionaire-maker at today’s price? Here are my thoughts.

What does Filtronic do?

The company designs and manufactures radio frequency communications products for the aerospace, defence, space, and telecommunications markets. Its FTSE 350 defence customers include BAE Systems and QinetiQ.

However, it’s the SpaceX partnership I find eye-catching here. Elon Musk’s privately held business runs satellite constellation Starlink, the world’s most advanced internet system. It provides high-speed, low-latency access even in the world’s most remote locations and now has over 4.6m subscribers.

In April 2024, Filtronic announced a five-year commercial agreement to supply E-band solid state power amplifiers for Starlink. These boost the power of weak signals. Then in August, it bagged a sizeable follow-on order from SpaceX.

As one of the world’s most innovative and mission-driven companies, SpaceX is notoriously picky about the suppliers it deals with. I recommend Elon Musk, the authorised biography by Walter Isaacson, to get a sense of the company’s relentless cost controls. It’s very vertically integrated.

So I see these deals as a very strong endorsement of the firm’s specialist products. They reinforce Filtronic’s position as a trusted supplier of best-in-class technology.

Rapid growth

Yesterday, the firm said that order intake in the current financial year (ending in May) is at “a higher rate than anticipated“. Consequently, trading was ahead of expectations, the second such announcement inside a month.

We won’t get the half-year results until 4 February. But analysts have been busily revising their figures, with most now forecasting £48m in revenue this year. If correct, that would represent a substantial 89% rise over last year’s £25.4m.

But what about profits? Well, broker Edison sees pre-tax profits skyrocketing from £3.4m to £11.5m — 238% year-on-year growth! So Filtronic is currently a fast-growing company.

Booming space sector

Yesterday, Blue Origin delayed the launch of its 320-foot-tall New Glenn rocket. The Jeff Bezos-owned company is helping Amazon build out its own internet service, Project Kuiper, to compete with Starlink.

In future, Starlink plans to have as many as 42,000 satellites in its mega-constellation, up from around 6,874 working ones today. This all shows the high-growth potential of the space sector.

I’m tempted

As for risks, the big one would be a deterioration in the SpaceX relationship. That would likely hurt the firm’s growth — and share price — very negatively.

Also, the forward price-to-sales (P/S) multiple is approximately 4.5, which is high. It tells me the stock probably isn’t going to generate millionaire-making gains, at least not within a £20,000 ISA.

Nevertheless, I’m tempted to take a small starter position here. Filtronic offers an interesting way to indirectly gain exposure to SpaceX’s growth.