I already had a pair of handcuff bought many years ago so I purchased these so i could handcuff each arm individually to my bed's metal side rails. Like most of the others here, I found myself quite surprised to see the thickness of the metal links and cuffs. these cuffs are heavier in weight, the keys are nice 3D keys, not the flat things you get with most beginner cuffs. As someone's who's been a Dom for 10 years, I can honestly say these can hold up to serious play if closed tight around the wrists. They thick links work well for clipping leather cuff to the links or tie rope around the links to further restrain. very versatile, everyone should have a set!