Abstract: A rotating yarn control element comprises a hub portion with a number of pins spaced around the periphery of the hub portion to define for the yarn a zig-zag path which degenerates with increasing distance from the axis of rotation of the element into a line path lying in a reference plane of the element. In use, with the element rotating about its axis and the yarn passing through the path defined by the guide surfaces, the total area of contact between the guide surfaces and the yarn will depend on the distance of the yarn from the axis of rotation of the element. This in turn determines whether the element operates in the "freewheeling" mode, the "positive grip" mode or the "yarn metering" mode. Other embodiments are described in which the element is formed by an injection moulding technique and the zig-zag path is presented by tooth like projections or by a channel in a drum member. A means for varying the amount of wrap around the element is also described.