In Japan, the formal Tsuru wa (string loop) is red for the top one and white for the below one,
to symbolize the sun and moon.
So, the color is the same for different sizes of tsuru.
For synthetic Tsuru, there are various colors manufactured.
They are done so because it is more efficient for production lines to accelerate production.
Thuru sold in our on-line shop, such as asathuru and kouzan-miyabi(向山-雅) are all in red and white only for all sizes.