I purchased these replacement bands for my Fitbit Charge 2 without realizing that they were size Large. I need the smaller size. I used the blue band for awhile until I purchased the correct size of wristband for myself. The grey wristband has never been worn or used. These are not genuine Fitbit bands but they fit perfectly. I could not tell them apart from the genuine small size I purchased (other than the size difference). They both have a metal buckle clasps and, as shown in the photo, one half is about 4" and the other half about 5". From a clean and smoke-free home.