Compatibility: Wepro Apple Watch straps is Seamlessly fit with iWatch Series 9 8 7 6 5 4 3 2 1, Apple Watch SE/Ultra. Apple Watch 41mm 45mm 40mm 38mm 44mm 42mm 49mm strap only, no Apple watch included Material: The iWatch strap is made of durable nylon, which is stretchy and elastic, stay away from the worry of too tight or too loose. When you wear it for sport/ daily life/ working, it is soft and breathable Design: This Apple Replacement Strap buckle is stainless steel metal design, the strap is stretchy. So you have two ways to put on and off, not so easy to become loose Size reference: The size of this Apple Watch wristband is normally apply to the people with 5.2"-8.8"(132mm-224mm). Simply put on or off, no sizes-choosing troubles, switch back and forth with a different color