High-potential penny stocks to consider buying for an ISA in October

A UK investing article argues that “penny stocks” can belong in a diversified Stocks and Shares ISA, warning they can also quickly swing from strong growth to major losses. It highlights Hardide (LSE:HDD), which the author says is up 1,262% over the past 12 months. The company uses a North American energy customer to coat engineering components against wear and corrosion; revenue is expected to rise to £13.5m this year from £4.7m in FY24, with projections of around £20m by FY28. The firm is building three new coating reactors. The piece also covers Made Tech (LSE:MTEC), noting revenue up 27% to £58.9m in the 12 months to 31 May and adjusted EBITDA up 69% to £5.9m, plus a four-year £40m contract signed in August. It cites a forward P/E of 12.5 for Hardide and begins to discuss Made Tech’s forward P/E at the end.