THESE ARE LARGER THAT STANDARD SHIRT STUDS IT IS A BOLD LOOK THAT IS BECOMING VERY POPULAR18MM BLACK ENAMEL BUTTON COVERS MOUNTED ON SILVER PLATED BEZEL SETTINGS WITH 5 MATCHING BREAST BTNS. GREAT WAY TO ENHANCE YOUR BUTTON CUFFS JUST SNAP THEM ON! WILL FIT AN STANDARD SHIRT BTN.