Steel weapons, mathematics with zero, stirrups, sailing ships, crossbow, plate and chainmail, castles, horse with horse-collar for power, amputations, crude prosthetics
Medieval (TL 3)
Nuclear power, computers, lasers, rockets, mag-lev monorail, hovercraft, kevlar, fission and hot fusion, solar power, organ transplants
With one specific
technology at: 1950-1990 (TL 7)