Two Bissell Microfiber floor duster refills

For sale are two packages of the Bissell microfiber floor duster refills. Each package contains one duster. The package doesn't indicate the size, but I'm guessing they fit the standard sized Bissell mop. I've never used them but am posting them as used because the packages have been stapled shut and there's a little brown thing in one of the packages (see photo). Thanks.