3,111. Holding Both Wool and Linen Reins

Hilchos Kilayim 10:20

A piece of leather, silk or other material that is attached to a person’s forehead with wool strings and linen strings, hanging over his face to deter flies, is not shaatnez because such a garment is not the way a person warms himself.

Hilchos Kilayim 10:21

One who is leading animals may hold their reins in his hand even if some of them are linen and some are wool. He may even wrap them around his hand, but if he ties the reins together, then they’re shaatnez and he may not wrap them around his hand.