Alexander Green is teasing another Elon Musk play through his Oxford Microcap Trader newsletter. The pitch calls it “Elon's Secret xPhone Partner — The Tiny Supplier SpaceX Can't Replace.”

The mystery company is Filtronic (FLTCF in the U.S. / FTC in London). And underneath the usual newsletter hype, there's actually an interesting story here. Filtronic is a small British company specializing in high-frequency filters and solid-state power amplifiers used in satellite communications. In 2024, it entered a strategic partnership with SpaceX.

But here's the part that caught my attention, SpaceX negotiated warrants giving it the ability to eventually own as much as 15% of Filtronic. That's a pretty serious relationship for a company currently valued around $750 million. SpaceX has also placed major orders for Filtronic's amplifiers to support Starlink's satellite network, with current contracts providing revenue visibility through roughly 2028. SpaceX is HUGE to this company, it recently represented around 70% of Filtronic's revenue.

Green takes it several steps further. He believes Musk is eventually going to introduce an AI-powered “xPhone” connected directly to Starlink, and that Filtronic's technology could become an important part of the infrastructure behind it. He's predicting the stock could 10X within 24 months.

I'm not buying that part of the pitch yet. The xPhone is still speculation, Filtronic is extremely dependent on one customer, and the valuation is already aggressive at roughly 15X revenue and 80X expected earnings. But forget the xPhone for a second, a ~$750M company already supplying critical technology to SpaceX, with SpaceX negotiating the right to own up to 15% of it, is interesting enough on its own.

This one is going on my watchlist.