These shirt cuffs belonged to John Wesley. They are made from fine cotton and embroidered with the initials 'IW', 'I' being the Roman version of the letter 'J'. The Roman alphabet was used quite commonly in the 1700s. The cuffs still bear a label from the 1800s.
Cuffs used to be shirt and sleeve protectors. They were separate from shirts, so they could be washed easily. Once worn out, cuffs could be disposed of separately from the shirt.