Kwa mac11 barrel question?

i was thinking about purchasing the kwa mac11 or m93 both of which are ns2 and was wondering which type of barrel each of them have so i no which kind of silencer i can put on them. Are they clockwise or anticlockwise. Also if you can recommend some good mock silencers for them. Also would the tokyo marui tracer unit be able to fit on it thank you.