After doing a bunch of research on old film cameras I found that many need obsolete batteries. Sometimes they use disposable batteries that have been discontinued and outlawed. This can be a real problem because these cameras require specific voltages. No battery. No shutter. (Some cameras like my Nikon F3 only use batteries for the light meter. Many need power to fire the shutter. ) So before you buy a camera on eBay check this page out. It’s a chart that could really help.