The inner side surface of the ball sleeve is contained outside the joint head in an insulating way to form a cardan joint.

球套内侧面吻合包含于关 节球面之外，形成万向节。

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Sleeve joint secures more than a pin joint, it's surface contact with the rim's inner wall is increased yet we're able to maintain it's lightweight properties.

袖套连接比销钉连接更加安全，可靠。这种表面与轮圈内部墙的接触更加增加了我们能维持它的轻量的特性。

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