This NBR rubber watch band with a curved end lug perfectly fit Seiko Sumo SBDC001, SBDC003, SBDC005 & Padi Sumo SBDC049 models, etc. NBR rubber has superior strength and more resistant than natural rubber to oils and acids. Material has met the RoHS requirements and rarely causes severe allergic reaction. Accompany with well-built stainless steel buckle and a featured big keeper. This item also includes one pair of FAT spring bars (eg. generic Seiko Dia. 2.5mm spring bar) to ensure a more secure connection. NBR rubber watch band is a good choice of Seiko replacement watch band for your Sumo SBDC001, SBDC003, SBDC005 & Padi Sumo SBDC049 models.