threading, so no messing around with tweezers or having to thread it it in a specific order. Babylock no longer makes it. They came out with a new model, Evolution, last August. The Evolution threads 2 threads at once with the jet aire threading system. The machines are pricey, but a delight to use because of the threading system and no tensions to mess with. You can probably pickup a used Evolve much cheaper now that Evolution is available.