Housing actuated derailleur. Extremely smooth. Another Gecko innovation. The housing should be nearly straight when in the large chainring. Delrin housing stop should be 1/2" from cable clamp bolt when in big chainring.  Most models have cable clamp bolt on BB. The Delrin stop can be a little further away from bolt. Don't put the Delrin stop closer than 2" from Derailleur cable clamp. The further away from derailleur the smoother the operation.