SWAP IN SECONDS: Swap daily to compliment your wardrobe or mix and match with BARTONs silicone quick release bands to take your timepiece from the workplace to the gym. Simply slide quick release knob with finger as shown in diagram. SELECT PROPER WIDTH: Compatible with any traditional or smart watch that uses 19mm spring bars. Quick release spring bars are included with and integrated into the band, so it is important that your watch's lug width matches exactly. Measure width where band meets the watch casing. You can also find the specifications for most watches by searching online. After determining proper width, click your heels three times and select the corresponding width from the menu above. TOP GRAIN & IDEAL COMFORT: Hand selected top grain leather with 316 stainless steel buckle. Treated underside is ultra-soft against the skin and minimizes slipping while providing ideal comfort. OPTIMAL FIT: Approximately 8" total length when not attached to watch; Designed to fit wrists 5.75" to 8", but watch geometry also impacts fit.