This is a Watch Protector Glass Guard. It's a protector that you thread onto the strap to protect the glass. It is currently out of production. It is deadstock. It is a large size. It fits up to about 22mm. The color is black. It can be used widely, from divers' watches to automatic and manual winding watches, and even regular watches. How about using it for everyday wear? It's lovely (*^^*) I am decluttering, so I am selling many items I collected in the past and watches with unconfirmed functionality!! Please be sure to check my profile before purchasing. This is a glass guard to prevent scratches on the watch glass. Please use it by threading it onto the strap. It is deadstock, but it is a product from several decades ago, so please understand. It is a large size. It's especially recommended for the upcoming summer (*^*)