Designed specifically for use with their Digiscoping VPA Variable Phone Adapter, this Swarovski Optik VPA AR-B Adapter Ring simply screws onto the VPA and is used to mount it onto your CL Companion, EL, EL Range, SLC binoculars, or the BTX spotting scope bino-viewer. The ring push-fits onto the optic's eyecups and optically centers your phone's