The Apple Watch Classic Buckle was made in two sizes and fit wrists measuring 130–195 mm (38 mm version) and 150–215 mm (42 mm version). Apple described this band as a traditional design “made from a calf leather that ages naturally over time to acquire a beautiful patina. A contrasting interior lining creates a dramatic two-tone look, and the color-matched edge stitching provides a subtle complement.”
This version of the Classic Buckle is the third generation of the design (the fourth generation added a spring-loaded square buckle to make it easier to insert the band). Its color is Red, but the band is not part of Apple’s (PRODUCT)RED collection.
In this example the Red Classic Buckle is paired with an Apple Watch Series 7 in silver stainless steel.
Sources: Apple, Bandbreite app