Zhik is simply the sponsor. They make sailing gear and probably just had a sticker on the moth you saw. Moth manufacturers are companies such as Bladerider and Mach 2. From the Bladerider website
Q. How much wind do you need to lift out of the water?
A. The average skipper weighs approximately 70kgs (154lbs) and will lift out of the water in 6 knots of
wind. A heavier skipper would weigh approximately 90kgs (198lbs) and will lift out of the water in approximately 8 knots of wind.
Q. What is the minimum and maximum sailor weight?
A. Ideally the sailor should not be less than 50kg and not more than 90kg. However based on our own tests, it is possible to sail and fly the Bladerider even if you are as light as 40kg and as heavy as 100kg.