SEIKO Third-Party Silicone Rubber Belt For Prospex and other rubber diver's watches Lug width: 22mm I purchased this as a spare for my Diver Scuba Marine Master, but I'm selling it, so I no longer need it. I am selling it. I often get asked if it's silicone or urethane, but I'm not an expert, so I can't accurately determine the material details, but I purchased it as silicone based on the HP where I bought it. Please refrain from price negotiations. I cannot accept questions after purchase. Please make sure to check the product details carefully. I try to ship as soon as possible, but I am not a delivery company. Please refrain from requesting date-specific shipping, as it may lead to trouble. Color: Black Diver Scuba Marine Master SEIKO 5 Sports Diver's Watch PROSPEX