Leather Apple Watch straps give your watch the look of a classic watch. This way, you can also wear Apple Watch to a business appointment or a fancy party. Leather watch straps for the Apple Watch come in many different colors and shapes. When choosing a strap, make sure you choose the right size for your Apple Watch. The Apple Watch 38, 40, 41, and 42mm straps fit on each of these sizes. The Apple Watch 44, 45, 46, and 49mm straps fit on each of those sizes.