313 Thin Alligator Grain Watch Strap this flat, stitched, alligator grain, leather watch strap is available in both black and brown. This is a classic look and will suit just about any watch. It is flat and thin, making it quite comfortable to wear. This watch strap is available in a variety of sizes. The lug and buckle measurements are as follows: 22mm/18mm, 24mm/20mm.