Nowadays, many Muslim youth tie and wear a black thread, chain, or bracelet on their wrists. If wearing or tying these things is based on a false belief, meaning that benefit is derived from them, then it is Haram (forbidden). And if it is merely for the sake of adornment, then it is Makruh Tahrimi. (Aham Masail / Vol: 1 / Pg: 21)