I used an Air Tag that fit into a silicone band that looked like a watch wrist band. My husband was used to wearing a watch however could no longer tell time on watch face whether clock or digital. Using my iPhone and Find My, I was able to track his progress on walking trails and could also be notified by sound when Left Behind when with me and he wandered away. The closure was difficult for him to understand how to remove it as the end was tucked through a slot and lay inside the wrist band (see photo). It was on except during showering which I helped him with and was one of the most helpful items I had purchased to address his safety. I do not recall where I purchased it from but have included pictures.